bluuebunny/crossref_metadata_2025 huggingface dataset:
Making connections: nationwide implementation of video telehealth tablets to address access barriers in veterans
Authors: Zulman Donna M , Wong Emily P , Slightam Cindie , Gregory Amy , Jacobs Josephine C , Kimerling Rachel , Blonigen Daniel M , Peters John , Heyworth Leonie
Published: August 2019

Background

Video telehealth technology has the potential to enhance access for patients with clinical, social, and geographic barriers to care. We evaluated the implementation of a US Department of Veterans Affairs (VA) initiative to distribute tablets to high-need Veterans with access barriers.

Methods

In this mixed methods implementation study, we examined tablet adoption (ie, facility-level tablet distribution rates and patient-level tablet utilization rates) and reach (ie, sociodemographic and clinical characteristics of tablet recipients) between 5/1/16 and 9/30/17. Concurrently, we surveyed 68 facility telehealth coordinators to determine the most common implementation barriers and facilitators, and then conducted interviews with telehealth coordinators and regional leadership to identify strategies that facilitated tablet distribution and use.

Results

86 VA facilities spanning all 18 geographic regions, distributed tablets to 6 745 patients. Recipients had an average age of 56 years, 53% lived in rural areas, 75% had a diagnosed mental illness, and they had a mean (SD) of 5 (3) chronic conditions. Approximately 4 in 5 tablet recipients used the tablet during the evaluation period. In multivariate logistic regression, tablet recipients were more likely to use their tablets if they were older and had fewer chronic conditions. Implementation barriers included insufficient training, staffing shortages, and provider disinterest (described as barriers by 59%, 55%, and 33% of respondents, respectively). Site readiness assessments, local champions, licensure modifications, and use of mandates and incentives were identified as strategies that may influence widespread implementation of home-based video telehealth.

Conclusion

VA’s initiative to distribute video telehealth tablets to high-need patients appears to have successfully reached individuals with social and clinical access barriers. Implementation strategies that address staffing constraints and provider engagement may enhance the impact of such efforts.
The ‘upper deck view’ improves visualization during acetabuloplasty without chondro-labral detachment
Authors: Ortiz-Declet Victor , Mu Brian H , Yuen Leslie C , Maldonado David R , Chen Austin W , Lall Ajay C , Domb Benjamin G
Published: August 2019

The ‘upper deck’ view is an arthroscopic perspective which visualizes the labral–osseous junction without detachment of the chondro-labral junction. The aim of this study was to evaluate the utility of the ‘upper deck’ view in preventing incomplete acetabuloplasty. Data were prospectively collected from September 2016 to November 2016 for all hip arthroscopies. We recorded the amount and clock-face of residual pincer-lesion acetabular bone resected using the ‘upper deck’ view. We noted whether this residual pincer-lesion acetabular bone was visible fluoroscopically, as well as the amount and clock-face of the overall acetabuloplasty. During the study period, 87 hip arthroscopies were performed; 50 met the inclusion criteria. Forty-six (92%) patients had residual pincer-lesion acetabular bone after completion of the acetabuloplasty resected from the bird's eye view. In all such cases the residual pincer-lesion acetabular bone was not visible under fluoroscopy and could only be detected using this specific view. The average maximum resection for the acetabuloplasty was 2.1 ± 0.9 and 1.4 ± 0.5 mm (P = 0.16) for resection of residual pincer-lesion acetabular bone. The ‘upper deck’ view provides the ability to decrease the risk of incomplete acetabuloplasty, due to the high likelihood (92%) of a residual beak of pincer-lesion acetabular bone when this view is not used during rim trimming.
Bhakti’s Visualities of Connection in the Arts Today
Authors: Pechilis Karen
Published: August 2019

Recently, artists in drama, dance, and contemporary art have visually evoked bhakti through their engagement with the historically remote Tamil bhakti poet-saint Kāraikkāl Ammaiyār. For centuries, bhakti in regional languages has been deeply intertwined with the arts, with its emphasis on personal engagement, emotionally inflected expressiveness and declarative performance. The bhakti poet-saints’ own words and deeds promoted a visuality of connection that enabled new and diverse participation in religio-social authority. Drawing on a resonant yet transformed mode of this visuality of connection, the arts today assert that Kāraikkāl Ammaiyār is a socially relevant figure—teacher, feminist, global spiritual icon—grounded in her own time and as speaking to ours. The contemporary arts’ mediation of classical ideas and contemporary concerns through visualities of connection that engage audiences today suggests a challenge to contemporary museum culture, which shares with the arts immersive display, yet grapples with envisioning a visuality of connection that provides a global audience today with an experience of classical art of India as both accessible and relevant.
Surgical management of post-infarction ventricular septal defect, mitral regurgitation and ventricular aneurysm
Authors: Belete Samuel , Punjabi Karan , Afoke Jonathan , Anderson Jonathan
Published: August 2019

A 49-year-old diabetic male was admitted to a hospital in 2018 following a 3-week history of worsening dyspnoea and pedal oedema. Early review and investigations indicated acute heart failure. Transthoracic echocardiogram (TTE) revealed mitral regurgitation (MR), aneurysmal change of the ventricles, a ventricular septal defect (VSD) and systolic dysfunction. Coronary angiogram demonstrated a significant left anterior descending and right coronary artery disease. He was diagnosed with a late presenting myocardial infarction (MI) with secondary mechanical complications. Mechanical complications of MI frequently require surgical intervention. The patient underwent a repair of VSD, mitral valve repair, excision of aneurysmal segment and coronary artery bypass grafting. Post-operative recovery was complicated by a sternal wound infection managed in conjunction with the plastic surgeons. A post-operative TTE showed a repaired ventricular septum and no residual MR. Early recognition and appropriate medical optimisation are required to achieve good patient outcomes.
The Human Right to Gender Identity: From the International Human Rights Scenario to Latin American Domestic Legislation
Authors: Arrubia Eduardo J
Published: August 2019

Transgender persons usually undergo significant discrimination all over the world. This is the reason why gender identity has been translated into the language of International Human Rights Law. Thus, the European Court of Human Rights has evolved along the last decades towards the recognition of this human right, and so has the Inter-American Court by releasing its recent advisory opinion on gender identity, equality and non-discrimination of same sex couples. Within this framework, some Latin American countries have passed regulations entitling trans persons to have their public records as regards their name, sex marker and image data modified. Nevertheless, these juridical norms of domestic law might not entirely comply with the standards that have been set by the Inter-American Court of Human Rights since they tend to reproduce cultural patterns of gender which lead to a pathological comprehension of transgenderism. In this analysis, Argentinian legislative experience is accounted for as a cutting-edge exemption in this matter.
Environmental effects on halo abundance and weak lensing peak statistics towards large underdense regions
Authors: Higuchi Yuichi , Inoue Kaiki Taro
Published: August 2019

The cosmic microwave background (CMB) contains an anomalous cold spot with a surrounding hot ring, known as the Cold Spot. Inoue & Silk proposed that this feature could be explained by postulating a supervoid: if such a large underdense region exists, then the growth of matter perturbing around the spot might differ from the average value in the Universe and the differences might affect weak lensing analysis of peak statistics. To investigate environmental effects on halo number count and peak statistics, we used a publicly available ray-tracing simulation for a box size of 2250 h−1 Mpc on a side. We found that the number count for massive haloes towards the largest underdense region in the simulation decreases and the corresponding significance of the difference, based on a cosmic average, is ≥3σ. On the basis of the results of peak statistics analysis, the number of high peaks decreases with the decrement of massive haloes, but the number of low peaks increases with the lack of matter in the line of sight. The highest significance of the decrement in peak counts in large underdense regions is 5σ in the total signal-to-noise ratio. Our result implies that environmental effects on halo abundance and weak lensing peak statistic can be used to probe the presence and properties of supervoids.
Structure of the primed state of the ATPase domain of chromatin remodeling factor ISWI bound to the nucleosome
Authors: Chittori Sagar , Hong Jingjun , Bai Yawen , Subramaniam Sriram
Published: August 2019

ATP-dependent chromatin remodeling factors of SWI/SNF2 family including ISWI, SNF2, CHD1 and INO80 subfamilies share a conserved but functionally non-interchangeable ATPase domain. Here we report cryo-electron microscopy (cryo-EM) structures of the nucleosome bound to an ISWI fragment with deletion of the AutoN and HSS regions in nucleotide-free conditions and the free nucleosome at ∼ 4 Å resolution. In the bound conformation, the ATPase domain interacts with the super helical location 2 (SHL 2) of the nucleosomal DNA, with the N-terminal tail of H4 and with the α1 helix of H3. Density for other regions of ISWI is not observed, presumably due to disorder. Comparison with the structure of the free nucleosome reveals that although the histone core remains largely unchanged, remodeler binding causes perturbations in the nucleosomal DNA resulting in a bulge near the SHL2 site. Overall, the structure of the nucleotide-free ISWI-nucleosome complex is similar to the corresponding regions of the recently reported ADP bound ISWI-nucleosome structures, which are significantly different from that observed for the ADP-BeFx bound structure. Our findings are relevant to the initial step of ISWI binding to the nucleosome and provide additional insights into the nucleosome remodeling process driven by ISWI.
AT-dinucleotide rich sequences drive fragile site formation
Authors: Irony-Tur Sinai Michal , Salamon Anita , Stanleigh Noemie , Goldberg Tchelet , Weiss Aryeh , Wang Yuh-Hwa , Kerem Batsheva
Published: August 2019

Common fragile sites (CFSs) are genomic regions prone to breakage under replication stress conditions recurrently rearranged in cancer. Many CFSs are enriched with AT-dinucleotide rich sequences (AT-DRSs) which have the potential to form stable secondary structures upon unwinding the double helix during DNA replication. These stable structures can potentially perturb DNA replication progression, leading to genomic instability. Using site-specific targeting system, we show that targeted integration of a 3.4 kb AT-DRS derived from the human CFS FRA16C into a chromosomally stable region within the human genome is able to drive fragile site formation under conditions of replication stress. Analysis of >1300 X chromosomes integrated with the 3.4 kb AT-DRS revealed recurrent gaps and breaks at the integration site. DNA sequences derived from the integrated AT-DRS showed in vitro a significantly increased tendency to fold into branched secondary structures, supporting the predicted mechanism of instability. Our findings clearly indicate that intrinsic DNA features, such as complexed repeated sequence motifs, predispose the human genome to chromosomal instability.
Antagonistic and synergistic epigenetic modulation using orthologous CRISPR/dCas9-based modular system
Authors: Josipović Goran , Tadić Vanja , Klasić Marija , Zanki Vladimir , Bečeheli Ivona , Chung Felicia , Ghantous Akram , Keser Toma , Madunić Josip , Bošković Maria , Lauc Gordan , Herceg Zdenko , Vojta Aleksandar , Zoldoš Vlatka
Published: August 2019

Establishing causal relationship between epigenetic marks and gene transcription requires molecular tools, which can precisely modify specific genomic regions. Here, we present a modular and extensible CRISPR/dCas9-based toolbox for epigenetic editing and direct gene regulation. It features a system for expression of orthogonal dCas9 proteins fused to various effector domains and includes a multi-gRNA system for simultaneous targeting dCas9 orthologs to up to six loci. The C- and N-terminal dCas9 fusions with DNMT3A and TET1 catalytic domains were thoroughly characterized. We demonstrated simultaneous use of the DNMT3A-dSpCas9 and TET1-dSaCas9 fusions within the same cells and showed that imposed cytosine hyper- and hypo-methylation altered level of gene transcription if targeted CpG sites were functionally relevant. Dual epigenetic manipulation of the HNF1A and MGAT3 genes, involved in protein N-glycosylation, resulted in change of the glycan phenotype in BG1 cells. Furthermore, simultaneous targeting of the TET1-dSaCas9 and VPR-dSpCas9 fusions to the HNF1A regulatory region revealed strong and persistent synergistic effect on gene transcription, up to 30 days following cell transfection, suggesting involvement of epigenetic mechanisms in maintenance of the reactivated state. Also, modulation of dCas9 expression effectively reduced off-target effects while maintaining the desired effects on target regions.
Discrimination as an Individual Wrong
Authors: Foran Michael P
Published: August 2019

This article argues that anti-discrimination rights are individual rights to be free from wrongful treatment and do not directly advance group-based interests or prohibit group-based harm. In light of this, a number of recurring accounts of the wrong of discrimination, particularly the wrong of indirect discrimination, are unsustainable. Claims that indirect discrimination is concerned with harm that is done to social groups or that laws prohibiting indirect discrimination seek to reduce or eliminate advantage gaps between social groups must be rejected as inaccurate. While principles of non-discrimination and principles of affirmative action often operate harmoniously to foster respect for the moral equality of persons, they each have a general affinity with distinct ethical traditions: deontology and teleology respectively. As such, we should conclude that indirect discrimination provisions are examples of formal and not substantive equality. Where rights to non-discrimination conflict with telic equality goals, UK law protects the rights of the individual.
Biotic response to the environmental and climatic variability in a deep alpine lake (Lake Lugu) over the last 30 000 years in southwest China
Authors: Wang Qian , Hamilton Paul B , Kattel Giri , Kong Lingyang
Published: August 2019

Multiple biogeochemical variables in a sediment core from Lake Lugu in southwest China were studied to investigate the effects of regional environmental changes on the ecosystem. Subfossil Cladocera, together with diatom, pollen and geochemical records, were used to examine climate-induced changes in lake ecosystem since the Last Glacial Maximum (30 000–0 cal year BP). Consistency among these biological records indicates that the succession of zooplankton, algae and vegetation changed in response to direct and indirect climatic factors. Alterations in the nutrient supply mediated by climate-induced changes in vegetation and soil processes are likely responsible for the variability of cladocerans. During the Last Glacial Maximum, cladocerans were dominated by littoral taxa (e.g. Alona), indicating an unproductive and oligotrophic lake system. A peak distribution in the pelagic Bosmina highlights the period of increased nutrient availability at 11 500 cal year BP. The ecological changes in Cladocera at 19 000 cal year BP and diatom communities at 18 000 cal year BP reveal independent and indirect responses to nutrient and light conditions induced by solar radiation and increased monsoon intensity across the study region. The palaeoecological archives from Lake Lugu sediments highlight a complex lake ecosystem influenced by both direct and indirect changes corresponding to climate changes and shifts in regional anthropogenic pressure over the last 30 000 years.
Secretory anti-citrullinated protein antibodies in serum associate with lung involvement in early rheumatoid arthritis
Authors: Roos Ljungberg Karin , Joshua Vijay , Skogh Thomas , Eklund Anders , Sköld C. Magnus , Karimi Reza , Nyrén Sven , Svärd Anna , Catrina Anca I , Kastbom Alf
Published: August 2019

Objective

A ‘mucosal connection’ in RA presently attracts increasing attention. We recently described the occurrence of secretory antibodies to citrullinated protein (SC-ACPA) in sera from patients with recent-onset RA. The current study was performed to evaluate possible associations between serum levels of secretory ACPA and signs of lung involvement in patients with early, untreated RA.

Methods

One hundred and forty-two RA patients were included as part of the ‘LUng Investigation in newly diagnosed RA’ study. One hundred and six patients were examined with high-resolution CT (HRCT) and 20 patients underwent bronchoscopy, where bronchial biopsies and bronchoalveolar lavage fluid (BALF) samples were obtained. SC-ACPA in serum and BALF were detected by an enzyme-linked immunoassay. Antibody levels were related to smoking history, pulmonary function, HRCT, BALF cell counts and findings in bronchial biopsies.

Results

SC-ACPA occurred in 16% of the serum samples and in 35% of the BALF samples. SC-ACPA levels in serum correlated with SC-ACPA levels in BALF (σ = 0.50, P = 0.027) and were higher among patients with HRCT parenchymal lung abnormalities (P = 0.022) or bronchiectasis (P = 0.042). Also, ever smoking was more frequent among serum SC-ACPA-positive patients (91% vs 67%, P = 0.023), and the SC-ACPA levels correlated with the number of pack-years (σ=0.20, P = 0.020).

Conclusion

In early, untreated RA, serum levels of SC-ACPA reflect lung involvement in terms of local ACPA levels, smoking and lung abnormalities on HRCT. These findings strengthen the link between mucosal ACPA responses and the lungs in RA.
Characterization of Estrogenic and Androgenic Activities for Bisphenol A-like Chemicals (BPs): In Vitro Estrogen and Androgen Receptors Transcriptional Activation, Gene Regulation, and Binding Profiles
Authors: Pelch Katherine E , Li Yin , Perera Lalith , Thayer Kristina A , Korach Kenneth S
Published: August 2019

Bisphenol A (BPA) is a high production volume chemical widely used in plastics, food packaging, and many other products. It is well known that endocrine-disrupting chemicals might be harmful to human health due to interference with normal hormone actions. Recent studies report widespread usage and exposure to many BPA-like chemicals (BPs) that are structurally or functionally similar to BPA. However, the biological actions and toxicity of those BPs are still relatively unknown. To address this data gap, we used in vitro cell models to evaluate the ability of 22 BPs to induce or inhibit estrogenic and androgenic activity. BPA, Bisphenol AF (BPAF), bisphenol Z (BPZ), bisphenol C (BPC), tetramethyl bisphenol A (TMBPA), bisphenol S (BPS), bisphenol E (BPE), 4,4-bisphenol F (4,4-BPF), bisphenol AP (BPAP), bisphenol B (BPB), tetrachlorobisphenol A (TCBPA), and benzylparaben (PHBB) induced estrogen receptor (ER)α and/or ERβ-mediated activity. With the exception of BPS, TCBPA, and PHBB, these same BPs were also androgen receptor (AR) antagonists. Only 3 BPs were found to be ER antagonists. Bisphenol P (BPP) selectively inhibited ERβ-mediated activity and 4-(4-phenylmethoxyphenyl)sulfonylphenol (BPS-MPE) and 2,4-bisphenol S (2,4-BPS) selectively inhibited ERα-mediated activity. None of the BPs induced AR-mediated activity. In addition, we identify that the BPs can bind to ER or AR with varying degrees by a molecular modeling analysis. Taken together, these findings help us to understand the molecular mechanism of BPs and further consideration of their usage in consumer products.
Reversibility of Neuroimaging Markers Influenced by Lifetime Occupational Manganese Exposure
Authors: Edmondson David A , Ma Ruoyun E , Yeh Chien-Lin , Ward Eric , Snyder Sandy , Azizi Elham , Zauber S Elizabeth , Wells Ellen M , Dydak Ulrike
Published: August 2019

Manganese (Mn) is a neurotoxicant that many workers are exposed to daily. There is limited knowledge about how changes in exposure levels impact measures in magnetic resonance imaging (MRI). We hypothesized that changes in Mn exposure would be reflected by changes in the MRI relaxation rate R1 and thalamic γ-aminobutyric acid (GABAThal). As part of a prospective cohort study, 17 welders were recruited and imaged on 2 separate occasions approximately 2 years apart. MRI relaxometry was used to assess changes of Mn accumulation in the brain. Additionally, GABA was measured using magnetic resonance spectroscopy in the thalamic and striatal regions of the brain. Air Mn exposure ([Mn]Air) and cumulative exposure indexes of Mn (Mn-CEI) for the past 3 months (Mn-CEI3M), past year (Mn-CEI12M), and lifetime (Mn-CEILife) were calculated using personal air sampling and a comprehensive work history, whereas toenails were collected for analysis of internal Mn body burden. Finally, welders’ motor function was examined using the Unified Parkinson’s Disease Rating Scale (UPDRS). Median exposure decreased for all exposure measures between the first and second scan. ΔGABAThal was significantly correlated with ΔMn-CEI3M (ρ = 0.66, adjusted p = .02), ΔMn-CEI12M (ρ = 0.70, adjusted p = .006), and Δ[Mn]Air (ρ = 0.77, adjusted p = .002). ΔGABAThal significantly decreased linearly with ΔMn-CEI3M (quantile regression, β = 15.22, p = .02) as well as Δ[Mn]Air (β = 1.27, p = .04). Finally, Mn-CEILife interacted with Δ[Mn]Air in the substantia nigra where higher Mn-CEILife lessened the ΔR1 per Δ[Mn]Air (F-test, p = .005). Although R1 and GABA changed with Mn exposure, UPDRS was unaffected. In conclusion, our study shows that effects from changes in Mn exposure are reflected in thalamic GABA levels and brain Mn levels, as measured by R1, in most brain regions.
Allometric growth in meiofaunal invertebrates: do all kinorhynchs show homogeneous trends?
Authors: Cepeda Diego , Álamo David , Sánchez Nuria , Pardos Fernando
Published: August 2019

Allometry determines relevant modifications in metazoan morphology and biology and is affected by many different factors, such as ontogenetic constraints and natural selection. A linear mixed model approach and reduced major axis regression were used to explore evolutionary interspecific allometric trends between the total trunk length and the lengths of the segments and spines in the phylum Kinorhyncha at three taxonomic levels: the whole phylum, the class and the family. Statistically significant results were found in all the trunk segments, meaning that these body units grow proportionally correlated with the body, contrary to the results obtained for the spines. Developmental and morphophysiological constraints could lead to negative allometry in the first and last segments, because these body regions in kinorhynchs are essential to the implementation of some of the main biological functions, such as feeding and locomotion. The differential arrangement of cuticular appendages between the taxonomic groups considered seems to cause different evolutionary trends, because positive allometry may appear if a segment requires more space to accommodate a large number of organs and appendages, and vice versa. The presence of sexual dimorphism could also define positive allometry of a segment, owing to the need to harbour the sexually dimorphic appendages and their associated structures.
Donald Charlton Bradley. 7 November 1924—20 December 2014
Authors: Sullivan Alice C. , Thomas John Meurig
Published: August 2019

Don Bradley was a twentieth-century pioneer of inorganic chemistry. He opened up the field of metal alkoxides and defined the parameters controlling the aggregative and volatility properties of this class of compounds that later dictated their use as precursors for fabrication of metal oxide thin films. His legacy also included seminal contributions to our knowledge of structure and bonding in the compound classes of metal amides and metal imides. He made highly innovative contributions in the field of metal organic chemical vapour deposition (MOCVD) fabrication of III/V semiconductor thin films, both through synthesis of single source precursors and through synthesis of molecular vehicles for safe storage and delivery of pyrophoric precursors. A modest, witty and gentle man of great intellectual depth and generosity, he nurtured and encouraged the fledgling talent of his students and co-workers and enthusiastically incorporated new developments in terms of experimental and theoretical tools to provide ever deeper understanding. He was relentless in giving his time and effort to support his college, Queen Mary, and the University of London as well as scientific organizations such as the Royal Society, Royal Institution and Royal Society of Chemistry, performing a range of society- or divisional-level official roles at various times, and he even made time for board of governor roles in schools. Don was held in the highest of esteem by his friends and family, students, colleagues and fellow scientists from across the world.
Citrullination of pyruvate kinase by PADI1 and PADI3 regulates glycolysis and cancer cell proliferation
Authors: Coassolo Sebastien , Davidson Guillaume , Negroni Luc , Gambi Giovanni , Daujat Sylvain , Romier Christophe , Davidson Irwin
Published: August 2019

CHD3 and CHD4 are mutually exclusive ATPase subunits of the Nucleosome Remodelling and Deacetylation (NuRD) complex that regulates gene expression. CHD4 is essential for growth of multiple patient derived melanoma xenografts and for breast cancer. Here we show that CHD4 regulates expression of PADI1 (Protein Arginine Deiminase 1) and PADI3 in multiple cancer cell types modulating citrullination of three arginines of the allosterically-regulated glycolytic enzyme pyruvate kinase M2 (PKM2). Citrullination reprograms cross-talk between PKM2 ligands lowering its sensitivity to the inhibitors Tryptophan, Alanine and Phenylalanine and promoting activation by Serine. Citrullination thus bypasses normal physiological regulation by low Serine levels to promote excessive glycolysis defining a novel pathway regulating proliferation of melanoma and other cancer cells. We provide unique insight as to how conversion of arginines to citrulline impacts key interactions within PKM2 that act in concert to reprogram its activity as an additional mechanism regulating this important enzyme.
Sex differences in seizure at presentation in glioma population
Authors: Ranjbar Sara , Anderies Barrett J , Singleton Kyle W , Johnston Sandra K , Rickertsen Cassandra R , Sharma Akanshka , Porter Alyx B , Mrugala Maciej M , Hu Leland S , Mitchell J Ross , Rubin Joshua B , Swanson Kristin R
Published: August 2019

Seizures are common presenting symptoms of primary brain tumors. Mechanisms of epileptogenesis are still unknown and are believed to be multifactorial. Previous studies have indicated correlation of seizure with tumor location. Recent investigations of our group have shown image-based parameters have sex-specific implications for patient outcome. In this retrospective study, we examined the association of tumor location with the probability and risk of seizure in male and female glioma patients.
Multimerization of Zika Virus-NS5 causes a ciliopathy and forces premature neurogenesis
Authors: Saade Murielle , Ferrero Diego S , Blanco-Ameijeiras José , Gonzalez-Gobartt Elena , Ruiz-Arroyo Victor M , Martínez-Sáez Elena , Cajal Santiago Ramón y , Verdaguer Nuria , Martí Elisa
Published: August 2019

Zika virus (ZikV) is a flavivirus that infects neural tissues, causing congenital microcephaly. ZikV has evolved multiple mechanisms to restrict proliferation and enhance cell death, although the underlying cellular events involved remain unclear. Here we show that the ZikV-NS5 protein interacts with host proteins at the base of the primary cilia in neural progenitor cells, causing an atypical non-genetic ciliopathy and premature neuron delamination. Furthermore, in human microcephalic fetal brain tissue, ZikV-NS5 persists at the base of the motile cilia in ependymal cells, which also exhibit a severe ciliopathy. While the enzymatic activity of ZikV-NS5 appears to be dispensable, the Y25, K28 and K29 residues in the protein, that are involved in NS5-oligomerization, are essential for the localization and interaction with components of the cilium base, promoting ciliopathy and premature neurogenesis. These findings lay the foundation to develop therapies that target ZikV-NS5-multimerization, preventing the developmental malformations associated with congenital Zika syndrome
Myogenesis modelled by human pluripotent stem cells uncovers Duchenne muscular dystrophy phenotypes prior to skeletal muscle commitment
Authors: Mournetas Virginie , Massouridès Emmanuelle , Dupont Jean-Baptiste , Kornobis Etienne , Polvèche Hélène , Jarrige Margot , Gosselin Maxime R. F. , Manousopoulou Antigoni , Garbis Spiros D. , Górecki Dariusz C. , Pinset Christian
Published: August 2019

Duchenne muscular dystrophy (DMD) causes severe disability of children and death of young men, with an incidence of approximately 1/5,000 male births. Symptoms appear in early childhood, with a diagnosis made around 4 years old, a time where the amount of muscle damage is already significant, preventing early therapeutic interventions that could be more efficient at halting disease progression. In the meantime, the precise moment at which disease phenotypes arise – even asymptomatically – is still unknown. Thus, there is a critical need to better define DMD onset as well as its first manifestations, which could help identify early disease biomarkers and novel therapeutic targets.

In this study, we have used human induced pluripotent stem cells (hiPSCs) from DMD patients to model skeletal myogenesis, and compared their differentiation dynamics to that of healthy control cells by a comprehensive multi-omic analysis. Transcriptome and miRnome comparisons combined with protein analyses at 7 time points demonstrated that hiPSC differentiation 1) mimics described DMD phenotypes at the differentiation endpoint; and 2) homogeneously and robustly recapitulates key developmental steps - mesoderm, somite, skeletal muscle - which offers the possibility to explore dystrophin functions and find earlier disease biomarkers.

Starting at the somite stage, mitochondrial gene dysregulations escalate during differentiation. We also describe fibrosis as an intrinsic feature of skeletal muscle cells that starts early during myogenesis. In sum, our data strongly argue for an early developmental manifestation of DMD whose onset is triggered before the entry into the skeletal muscle compartment, data leading to a necessary reconsideration of dystrophin functions during muscle development.
Apolipoprotein A-I Mimetic 4F Peptide Generates Amyloid Cytotoxins by Forming Hetero-oligomers with β-amyloid
Authors: Sahoo Bikash Ranjan , Bekier Michael E. , Liu Zichen , Kocman Vojc , Stoddard Andrea K. , Anantharamaiah G. M. , Nowick James , Fierke Carol A. , Wang Yanzhuang , Ramamoorthy Ayyalusamy
Published: August 2019

Apolipoproteins are involved in pathological conditions of Alzheimer’s disease (AD), truncated apolipoprotein fragments and β-amyloid (Aβ) peptides coexist as neurotoxic heteromers within the plaques. Therefore, it is important to investigate these complexes at the molecular level to better understand their properties and roles in the pathology of AD. Here, we present a mechanistic insight into such heteromerization using a structurally homologue apolipoprotein fragment of apoA-I (4F) complexed with Aβ(M1-42) and characterize their toxicity. The 4F peptide slows down the aggregation kinetics of Aβ(M1-42) by constraining its structural plasticity. NMR and CD experiments identified 4F-Aβ(M1-42) heteromers as being comprised of unstructured Aβ(M1-42) and helical 4F. A uniform ≈2-fold reduction in Aβ4215N/1H NMR signal intensities with no observable chemical shift perturbation indicated the formation of a large complex, which was further confirmed by diffusion NMR experiments. Microsecond scale atomistic molecular dynamics simulations showed that 4F interaction with Aβ(M1-42) is electrostatically driven and induces unfolding of Aβ(M1-42). Neurotoxicity profiling of Aβ(M1-42) complexed with 4F confirms a significant reduction in cell-viability and neurite growth. The molecular architecture of heteromerization between 4F and Aβ(M1-42) discovered in this study provides evidence towards our understanding of the role of apolipoproteins or their truncated fragments in exacerbating AD pathology.
Organoid-derived Duodenum Intestine-Chip for preclinical drug assessment in a human relevant system
Authors: Kasendra Magdalena , Luc Raymond , Yin Jianyi , Manatakis Dimitris V. , Apostolou Athanasia , Sunuwar Laxmi , Obrigewitch Jenifer , Hamilton Geraldine A. , Donowitz Mark , Karalis Katia
Published: August 2019

Induction of intestinal drug metabolizing enzymes can complicate the development of new drugs, owing to potential to cause drug-drug interactions (DDIs) leading to changes in pharmacokinetics, safety and efficacy. The development of a human relevant model of the adult intestine that accurately predicts CYP450 induction could help address this challenge as species differences preclude extrapolation from animals. Here, we combined organoids and Organ-Chip technology to create a human Duodenum Intestine-Chip that emulates intestinal tissue architecture and functions, that are relevant for the study of drug transport, metabolism, and DDI. Duodenum Intestine-Chip demonstrates the polarized cell architecture, intestinal barrier function, presence of specialized cell subpopulations, and in vivo-relevant expression, localization, and function of major intestinal drug transporters. Notably, in comparison to Caco-2, it displays improved CYP3A4 expression and induction capability. This model could enable improved in vitro to in vivo extrapolation for better predictions of human pharmacokinetics and risk of DDIs.
Characterization of TAG-63 and its role on axonal transport inC. elegans
Authors: Bhan Prerana , Shanmugam Muniesh Muthaiyan , Wang Ding , Bayansan Odvogmed , Chen Chih-Wei , Wagner Oliver Ingvar
Published: August 2019

Model organisms are increasingly used to study and understand how neurofilament (NF)-based neurological diseases develop. However, whether a NF homolog exists inC. elegansremains unclear. We characterize TAG-63 as a NF-like protein with sequence homologies to human NEFH carrying various coiled coils as well as clustered phosphorylation sites. TAG-63 also exhibits features of NFL such as a molecular weight of around 70 kD, the lack of KSP repeats and the ability to form 10 nm filamentous structures in transmission electron micrographs. An anti-NEFH antibody detects a band at the predicted molecular weight of TAG-63 in Western blots of whole worm lysates and this band cannot be detected intag-63knockout worms. A transcriptionaltag-63reporter expresses in a broad range of neurons, and various anti-NFH antibodies stain worm neurons with an overlapping expression of axonal vesicle transporter UNC-104(KIF1A). Cultured neurons grow shorter axons when incubating with drugs known to disintegrate the NF network and rhodamine-labeledin vitroreconstituted TAG-63 filaments disintegrate upon drug exposure. Speeds of UNC-104 motors are diminished intag-63mutant worms with visibly increased accumulations of motors along axons. UNC-104/TAG-63 and SNB-1/TAG-63 not only co-localize in neurons but also revealed positive BiFC (bimolecular fluorescence assay) signals.
“Deciphering the amyloid foldome of TDP-43”
Authors: Mompeán Miguel , Buratti Emanuele , Laurents Douglas V.
Published: August 2019

TDP-43 is an essential regulator of RNA splicing and metabolism and its aggregates play key roles in devastating diseases, including Amyotrophic Lateral Sclerosis (ALS)1, Frontotemporal Dementia (FTD) and Limbic-Predominant Age-Related TDP-43 Encephalopathy (LATE)2. Besides this pathological aggregation, TDP-43’s oligomerization also serves vital functions3, which adds urgency to determine pathological conformations of TDP-43. The recently published cryo-EM study by Cao, Eisenberg and coworkers now reveals amyloid structures of putative pathological aggregates from TDP-43’s C-terminal region4. Whereas the Cao et al.’s cryo-EM structures contain both the hydrophobic and Q/N-rich segments, the data were interpreted mainly through the lens of hydrophobic contacts. However, the Q/N-rich region can form amyloid on its own5,6 and therefore additional considerations of the Q/N-rich segment’s contributions will advance our understanding of TDP-43 aggregation.
Dynamics of activating and repressive histone modifications in Drosophila neural stem cell lineages and brain tumors
Authors: Abdusselamoglu Merve Deniz , Landskron Lisa , Bowman Sarah K. , Eroglu Elif , Burkard Thomas , Kingston Robert E. , Knoblich Juergen A.
Published: August 2019

During central nervous system (CNS) development, spatiotemporal gene expression programs mediate specific lineage decisions to generate neuronal and glial cell types from neural stem cells (NSCs). However, little is known about the epigenetic landscape underlying these highly complex developmental events. Here, we perform ChIP-seq on distinct subtypes of Drosophila FACS-purified neural stem cells (NSCs) and their differentiated progeny to dissect the epigenetic changes accompanying the major lineage decisions in vivo. By analyzing active and repressive histone modifications, we show that stem cell identity genes are silenced during differentiation by loss of their activating marks and not via repressive histone modifications. Our analysis also uncovers a new set of genes specifically required for altering lineage patterns in type II neuroblasts, one of the two main Drosophila NSC identities. Finally, we demonstrate that this subtype specification in NBs, unlike NSC differentiation, requires Polycomb-group (PcG)-mediated repression.

Summary statement

Dynamic epigenetic landscape of Drosophila neural stem cell lineages.
Correction of Niemann-Pick type C1 disease with the histone deacetylase inhibitor valproic acid
Authors: Subramanian Kanagaraj , Hutt Darren M , Gupta Vijay , Mao Shu , Balch William E.
Published: August 2019

Niemann-Pick type C (NPC) disease is primarily caused by mutations in the NPC1 gene and is characterized by the accumulation of unesterified cholesterol and lipids in the late endosomal (LE) and lysosomal (Ly) compartments. The most prevalent disease-linked mutation is the I1061T variant of NPC1, which exhibits defective folding and trafficking from the endoplasmic reticulum to the LE/Ly compartments. We now show that the FDA-approved histone deacetylase inhibitor (HDACi) valproic acid (VPA) corrects the folding and trafficking defect associated with I1061T-NPC1 leading to restoration of cholesterol homeostasis, an effect that is largely driven by a reduction in HDAC7 expression. The VPA-mediated trafficking correction is in part associated with an increase in the acetylation of lysine residues in the cysteine-rich domain of NPC1. The HDACi-mediated correction is synergistically improved by combining it with the FDA-approved anti-malarial, chloroquine, a known lysosomotropic compound, which improved the stability of the LE/Ly-localized fraction of the I1061T variant. We posit that combining the activity of VPA, to modulate epigentically the cellular acetylome, with chloroquine, to alter the lysosomal environment to favor stability of the trafficked I1061T variant protein, can have a significant therapeutic benefit in patients carrying at least one copy of the I1061T variant of NPC1, the most common disease-associated mutation leading to NPC disease. Given its ability to cross the blood brain barrier, we posit VPA provides a potential mechanism to improve the response to 2-hydroxypropyl-β-cyclodextrin, by restoring functional NPC1 to cholesterol managing compartment as an adjunct therapy.
Origin of Conformational Dynamics in a Globular Protein
Authors: Damry Adam M. , Mayer Marc M. , Broom Aron , Goto Natalie K. , Chica Roberto A.
Published: August 2019

Protein structures are dynamic, undergoing specific motions that can play a vital role in function. However, the link between primary sequence and conformational dynamics remains poorly understood. Here, we studied how conformational dynamics can arise in a globular protein by evaluating the impact of individual substitutions of core residues in DANCER-3, a streptococcal protein G domain β1 (Gβ1) variant that we previously designed to undergo a specific mode of conformational exchange that has never been observed in the wild-type protein. Using a combination of solution NMR experiments and molecular dynamics simulations, we demonstrate that only two mutations are necessary to create this conformational exchange, and that these mutations work synergistically, with one destabilizing the native Gβ1 structure and the other allowing two new conformational states to be accessed on the energy landscape. Overall, our results show how conformational dynamics can appear in a stable globular fold, a critical step in the molecular evolution of new dynamics-linked functions.
Opposing immune and genetic forces shape oncogenic programs in synovial sarcoma
Authors: Jerby-Arnon Livnat , Neftel Cyril , Shore Marni E. , McBride Matthew J. , Haas Brian , Izar Benjamin , Weissman Hannah R. , Volorio Angela , Boulay Gaylor , Cironi Luisa , Richman Alyssa R. , Broye Liliane C. , Gurski Joseph M. , Luo Christina C. , Mylvaganam Ravindra , Nguyen Lan , Mei Shaolin , Melms Johannes c. , Georgescu Christophe , Cohen Ofir , Buendia-Buendia Jorge E. , Cuoco Michael S. , Labes Danny , Zollinger Daniel R. , Beechem Joseph M. , Nielsen G. Petur , Chebib Ivan , Cote Gregory , Choy Edwin , Letovanec Igor , Cherix Stéphane , Wagle Nikhil , Sorger Peter K. , Haynes Alex B. , Mullen John T. , Stamenkovic Ivan , Rivera Miguel N. , Kadoch Cigall , Rozenblatt-Rosen Orit , Suvà Mario L. , Riggi Nicolò , Regev Aviv
Published: August 2019

Synovial sarcoma is an aggressive mesenchymal neoplasm, driven by the SS18-SSX fusion, and characterized by immunogenic antigens expression and exceptionally low T cell infiltration levels. To study the cancer-immune interplay in this disease, we profiled 16,872 cells from 12 human synovial sarcoma tumors using single-cell RNA-sequencing (scRNA-Seq). Synovial sarcoma manifests antitumor immunity, high cellular plasticity and a core oncogenic program, which is predictive of low immune levels and poor clinical outcomes. Using genetic and pharmacological perturbations, we demonstrate that the program is controlled by the SS18-SSX driver and repressed by cytokines secreted by macrophages and T cells in the tumor microenvironment. Network modeling predicted that SS18-SSX promotes the program through HDAC1 and CDK6. Indeed, the combination of HDAC and CDK4/6 inhibitors represses the program, induces immunogenic cell states, and selectively targets synovial sarcoma cells. Our study demonstrates that immune evasion, cellular plasticity, and cell cycle are co-regulated and can be co-targeted in synovial sarcoma and potentially in other malignancies.
Arabidopsis ECERIFERUM3 (CER3) Plays a Critical Role in Maintaining Hydration for Pollen-Stigma Recognition during Fertilization
Authors: Xu Faqing , Li Xiaojing , Yang Zhongnan , Zhang Sen
Published: August 2019

ABSTRACT

Plants distinguish the pollen grains that land on their stigmas, only allowing compatible pollen to fertilize female gametes. To analyze the underlying mechanism, conditional male-sterile mutations with affected pollen coat and disrupted pollen-stigma recognition were isolated and described. The mutant pollen failed to germinate, but germinated in vitro, suggesting that they are viable. In mutants, stigma cells that contacted their own pollen generated callose, a carbohydrate produced in response to foreign pollen. High humidity restored pollen hydration and successful fertilization, indicating defective dehydration in pollen-stigma interaction. Further analysis results from mixed pollination experiments demonstrated that the mutant pollen specifically lacked a functional pollen-stigma recognition system. The sterile plants lacked stem waxes and displayed postgenital fusion between aerial floral organs. In addition, the mutant pollen was deficient in long-chain lipids and had excess tryphine. Transmission electron microscopy observation showed that mutant pollen had almost the same surface structure as the wild type at bicellular pollen stage. However, abnormal plastoglobuli were observed in the plastids of the mutant tapetum, which was indicative of altered lipid accumulation. CER3 transcript was found in anther tapetum and microspores at development stage 9 while CER3-GFP fusion protein was localized to the cell plasma membrane. Our data reveal that CER3 is required for biosynthesis of tryphine lipids which play a critical role in maintaining hydration for pollen-stigma recognition during fertilization.
Structure determination from lipidic cubic phase embedded microcrystals by MicroED
Authors: Zhu Lan , Bu Guanhong , Jing Liang , Shi Dan , Gonen Tamir , Liu Wei , Nannenga Brent L.
Published: August 2019

The lipidic cubic phase (LCP) technique has proved to facilitate the growth of high-quality crystals that are otherwise difficult to grow by other methods. Because crystals grown in LCP can be limited in size, improved techniques for structure determination from these small crystals are important. Microcrystal electron diffraction (MicroED) is a technique that uses a cryo-TEM to collect electron diffraction data and determine high-resolution structures from very thin micro and nanocrystals. In this work, we have used modified LCP and MicroED protocols to analyze crystals embedded in LCP. Proteinase K in LCP was used as a model system, and several LCP sample preparation strategies were tested. Among these, treatment with 2-Methyl-2,4-pentanediol (MPD) and lipase were both able to reduce the viscosity of the LCP and produce quality cryo-EM grids with well-diffracting crystals. These results set the stage for the use of MicroED to analyze other microcrystalline samples grown in LCP.