Targeting Cancer with CRISPR/Cas9-Based Therapy

Cancer is a devastating condition characterised by the uncontrolled division of cells with many forms remaining resistant to current treatment. A hallmark of cancer is the gradual accumulation of somatic mutations which drive tumorigenesis in cancerous cells, creating a mutation landscape distinctive to a cancer type, an individual patient or even a single tumour lesion. Gene editing with CRISPR/Cas9-based tools now enables the precise and permanent targeting of mutations and offers an opportunity to harness this technology to target oncogenic mutations. However, the development of safe and effective gene editing therapies for cancer relies on careful design to spare normal cells and avoid introducing other mutations. This article aims to describe recent advancements in cancer-selective treatments based on the CRISPR/Cas9 system, especially focusing on strategies for targeted delivery of the CRISPR/Cas9 machinery to affected cells, controlling Cas9 expression in tissues of interest and disrupting cancer-specific genes to result in selective death of malignant cells.

Information flow across the cortical timescales hierarchy during narrative comprehension

When listening to spoken narratives, we must integrate information over multiple, concurrent timescales, building up from words to phrases to sentences to a coherent narrative. Recent evidence suggests that the brain relies on a chain of hierarchically organized areas with increasing temporal receptive windows to process naturalistic narratives. In this study, we use inter-subject functional connectivity to reveal a stimulus-driven information flow along the cortical hierarchy. Using cross-correlation analysis to estimate the time lags between six functional networks, we found a fixed temporal sequence of information flow, starting in early auditory areas, followed language areas, the attention network, and lastly the default mode network. This gradient is consistent across eight distinct stories but absent in resting-state and scrambled story data, indicating that the lag gradient reflects the construction of narrative features. Finally, we simulate a variety of narrative integration models and demonstrate that nested narrative structure along with the gradual accumulation of information within the boundaries of linguistic events at each level of the processing hierarchy is sufficient to reproduce the lag gradient. Taken together, this study provides a computational framework for how information flows along the cortical hierarchy during narrative comprehension.

Multimorbidity Trajectory Classes as Predicted by Race, Ethnicity, and Social Relationship Quality

Growth mixture modeling was used to classify multimorbidity (≥2 chronic conditions) trajectories over a 10-year period (2006-2016) in the Health and Retirement Study (N = 7,151, mean age = 68.6 years). Race/ethnicity (non-Hispanic Black, Hispanic, non-Hispanic White) and social relationship quality (positive social support and negative social exchanges, such as criticisms) were then used to predict trajectory class membership, controlling for age, sex, education, and wealth. We identified three trajectory classes: initial low levels and rapid accumulation of multimorbidity (increasing: 12.6%), initial high levels and gradual accumulation of multimorbidity (high: 19.5%), and initial low levels and gradual accumulation of multimorbidity (low: 67.9%). Blacks were more than twice as likely to be in the increasing (OR = 2.04, CI[1.29,3.21]) and high (OR = 2.28 CI[1.58,3.206]) multimorbidity groups compared with Whites, but there were no significant differences between Hispanics and Whites for either trajectory class (OR = .84 CI[.47,1.51]and OR = .74 CI[.41,1.34], respectively). Increments in perceived support were associated with significantly lower risk of membership in the increasing (OR = .59, CI[.46,.78]) and high classes (OR = .54 CI[.42,.69]), and increments in negative exchanges were associated with significantly higher risk of membership in the increasing (OR = 1.64 CI[1.19,2.25]) and high classes (OR = 2.22 CI[1.64,3.00]). These results provide important new information for understanding health disparities and the role of social relationships associated with multimorbidity in middle and later life that may aid in identifying those most at risk and suggesting possible interventions for mitigating that risk.

Magnetic Topology in Coupled Binaries, Spin-orbital Resonances, and Flares

We consider topological configurations of the magnetically coupled spinning stellar binaries (e.g., merging neutron stars or interacting star–planet systems). We discuss conditions when the stellar spins and the orbital motion nearly “compensate” each other, leading to very slow overall winding of the coupled magnetic fields; slowly winding configurations allow gradual accumulation of magnetic energy, which is eventually released in a flare when the instability threshold is reached. We find that this slow winding can be global and/or local. We describe the topology of the relevant space F = T 1 S 2 as the unit tangent bundle of the two-sphere and find conditions for slowly winding configurations in terms of magnetic moments, spins, and orbital momentum. These conditions become ambiguous near the topological bifurcation points; in certain cases, they also depend on the relative phases of the spin and orbital motions. In the case of merging magnetized neutron stars, if one of the stars is a millisecond pulsar, spinning at ∼10 ms, the global resonance ω 1 + ω 2 = 2Ω (spin-plus beat is two times the orbital period) occurs approximately one second before the merger; the total energy of the flare can be as large as 10% of the total magnetic energy, producing bursts of luminosity ∼1044 erg s−1. Higher order local resonances may have similar powers, since the amount of involved magnetic flux tubes may be comparable to the total connected flux.

A high-density lineage tree reveals dynamics of expression differences accumulation in nondifferentiating clonal expansion

Differences in gene expression levels among genetically identical cells naturally accumulate during cellular proliferation, forming the basis of expression noise or differentiation. Nevertheless, how transcriptome-wide noise accumulation is constrained to maintain homeostasis during continuous cell divisions has remained largely unresolved. We developed a novel method named single-cell transcriptome and dense tree (STADT) to simultaneously determines the transcriptomes and lineage tree of >50% single cells in a single-cell-seeded colony. This lineage tree revealed gradual accumulation of transcriptome differences that became saturated upon four cell divisions, reduced expression noise for sub-tree/sub-colonies closer to inferred expression boundaries, and transcriptionally modulated co-fluctuations among genes. These results collectively showed, for the first time, constrained dynamics of expression noise in the context of cell division.

CLL-Derived Exosomes Turn Endothelial Cells into IL-6 Producing Cells

CLL is characterized by gradual accumulation of mature appearing long-lived lymphocytes that travel in blood and reside in lymph nodes, spleen and bone marrow. In these sites, pro inflammatory humoral factors support the survival and proliferation of the neoplastic cells. Previous studies showed that levels of the proinflammatory cytokine IL-6 are at least 10 folds higher in patients with CLL compared with healthy individuals. Yet, which cells produce and secrete IL-6 and what triggers this cellular activity in CLL is unknown. Secreted by all types of cells, exosomes are nano-scaled particles that travel in blood and carry a cargo that at least partially reflects the molecular makeup of its cell of origin. Exosomes, including those originating from neoplastic cells, function as stable intercellular transport vehicles that deliver their cargo to cells that engulf them. For example, CLL-derived exosomes are taken up by mesenchymal stromal cells, transforming them to cancer associated fibroblasts. Given the appropriate stimulation, endothelial cells produce IL-6 which provides CLL cells with a survival advantage. Therefore, we hypothesized that CLL-exosomes turn endothelial cells into "IL-6-secreting cells". To test this hypothesis, we transfected vein-derived (HUVECs) and arterial-derived (HAOEC) endothelial cells with exosomes that we isolated from the peripheral blood of 45 treatment naïve patients. We found that endothelial cells take-up CLL-exosomes in a dose- and time- dependent manner. Since CLL cells are protected from apoptosis in IL-6 rich environment, we wondered whether CLL-exosomes turn endothelial cells into IL-6-producing cells. To test this, we exposed endothelial cells to CLL-exosomes and found 50% increase in IL-6 levels, suggesting that the endothelial-exposed cells produced and secreted IL-6. Subsequently, we filtered out this growth medium and added CLL cells to this IL-6 enriched medium. After 15 minutes, STAT3 became phosphorylated and there was 40% decrease in the rate of apoptosis, indicating that IL-6 activated STAT3-dependent anti-apoptotic pathway. Phosphor-proteomics analysis of endothelial cells that were loaded with CLL-exosomes revealed 23 phosphor-proteins that were upregulated. Network analysis unraveled the central role of phosphor-b-catenin. To test whether b-catenin induces IL-6 in these cells, we transfected HUVECs with a b-catenin containing plasmid. We found by ELISA 30% increase in the levels of IL-6 in the culture medium and by chromatin immunoprecipitation assay an increased binding of 3 transcription factors (NFkB, LEF/TCF, and CEBP) to the IL-6 promoter. Taken together, we found that CLL cells communicate with endothelial cells through exosomes that they release. Once these exosomes are taken up by endothelial, they turn them into IL-6 producing cells, which in turn contributes to CLL cells' survival. Disclosures No relevant conflicts of interest to declare.

Spring ritual calendar of the ukrainians of the Republic of Moldova: source study and historiographic analysis

The carried out source analysis revealed that during the XIX, XX, and the early XXI centuries there was a gradual accumulation of the source base about the spring calendar of Moldovan Ukrainians. Articles, monographs, folklore collections, archival records, local periodicals, Internet portals, sites, as well as the author’s self-collected field materials are an important source for studying the problem of spring calendar holidays of the Ukrainian population of the Republic and allow them to be considered from a historical retrospective, to trace the connection with the mother Ukrainian culture, interethnic influences and transformations, to conduct a comparative analysis of old and new holidays and rituals, to consider the stages of transformation of their cultural content. The corpus of published and handwritten materials is a valuable source for further ethnological, ethno-linguistic, folklore and cultural studies. It makes possible to trace the originality and territorial and local differences of the Ukrainian ethno-culture on the territory of the Republic of Moldova, to identify the commonality of basic, allUkrainian, as well as distinctive, characteristic exclusively of the Ukrainians in Moldova, elements and features of the spring rituals.

Slowed canonical progress in large fields of science

In many academic fields, the number of papers published each year has increased significantly over time. Policy measures aim to increase the quantity of scientists, research funding, and scientific output, which is measured by the number of papers produced. These quantitative metrics determine the career trajectories of scholars and evaluations of academic departments, institutions, and nations. Whether and how these increases in the numbers of scientists and papers translate into advances in knowledge is unclear, however. Here, we first lay out a theoretical argument for why too many papers published each year in a field can lead to stagnation rather than advance. The deluge of new papers may deprive reviewers and readers the cognitive slack required to fully recognize and understand novel ideas. Competition among many new ideas may prevent the gradual accumulation of focused attention on a promising new idea. Then, we show data supporting the predictions of this theory. When the number of papers published per year in a scientific field grows large, citations flow disproportionately to already well-cited papers; the list of most-cited papers ossifies; new papers are unlikely to ever become highly cited, and when they do, it is not through a gradual, cumulative process of attention gathering; and newly published papers become unlikely to disrupt existing work. These findings suggest that the progress of large scientific fields may be slowed, trapped in existing canon. Policy measures shifting how scientific work is produced, disseminated, consumed, and rewarded may be called for to push fields into new, more fertile areas of study.

Prospects for the Use of Combined Lysozyme Drugs in COVID-19

According to statistics, 81% of cases of COVID-19 coronavirus infection occur in a mild or moderate form. These patients make up the main part of the flow of calls to a general practitioner at the moment. The difficulties that therapists face during a pandemic are associated with finding the optimal therapy for the disease due to the gradual accumulation of knowledge about a new RNA-containing virus. The article presents the data of a study of the antiviral activity of the drug Lysobact Complete® in vitro on a Vero cell culture. Studies of previous years confirm the antiviral, anti-inflammatory, strengthening local immunity effect of lysozyme hydrochloride, the antiviral effect of cetylpyridinium chloride, both are the components of the drug Lysobact Complete® dosed spray for topical use. This in vitro study confirmed the antiviral activity of the drug on the SARS-CoV-2 virus, which makes its use promising in complex therapy of patients with COVID-19. The theoretical justification of the practical use of the drug is given. The authors hope that the research data will be useful to doctors when providing medical care to patients with COVID-19

Mass of genes rather than master genes underlie the genomic architecture of amphibian speciation

The genetic architecture of speciation, i.e., how intrinsic genomic incompatibilities promote reproductive isolation (RI) between diverging lineages, is one of the best-kept secrets of evolution. To directly assess whether incompatibilities arise in a limited set of large-effect speciation genes, or in a multitude of loci, we examined the geographic and genomic landscapes of introgression across the hybrid zones of 41 pairs of frog and toad lineages in the Western Palearctic region. As the divergence between lineages increases, phylogeographic transitions progressively become narrower, and larger parts of the genome resist introgression. This suggests that anuran speciation proceeds through a gradual accumulation of multiple barrier loci scattered across the genome, which ultimately deplete hybrid fitness by intrinsic postzygotic isolation, with behavioral isolation being achieved only at later stages. Moreover, these loci were disproportionately sex linked in one group (Hyla) but not in others (Rana and Bufotes), implying that large X-effects are not necessarily a rule of speciation with undifferentiated sex chromosomes. The highly polygenic nature of RI and the lack of hemizygous X/Z chromosomes could explain why the speciation clock ticks slower in amphibians compared to other vertebrates. The clock-like dynamics of speciation combined with the analytical focus on hybrid zones offer perspectives for more standardized practices of species delimitation.