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Could shareholders inadvertently cancel their Shareholders Agreement?

Following the judgment in De Freitas v Chamdor Meat Packers [2015] JOL 33940 (GJ), when a company proposes to its shareholders the adoption of a new Memorandum of Incorporation, the shareholders should carefully consider the provisions of the new Me...




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What are the potential benefits of OTT?

Part 2 of 4 (a) For Users/Consumers Simply put, OTT services are low or free of charge services. Its known that online video traffic is on the growth due to simple accessibility and cheapness. Consumers’ hopes are also evolving as they are exp...




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Changes on the horizon in 2020: China and Hong Kong’s proposed reforms to data protection, cyber security and Internet content regulation

2020 looks set to be a significant year for privacy, cyber security and Internet content reforms in China and Hong Kong. On 20 December 2019, the Cyberspace Administration of China released the “Regulation on Governance of Internet Information...




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Sainsbury's / Asda and the CMA - a statement of intent pre-Brexit

On 21 and 20 February 2019 respectively the Competition and Markets Authority (CMA) published its Provisional Findings and a Full Article



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The position of the right of pledge after bankruptcy on goods that are delivered subject to retention of title

On 3 June 2016, the Supreme Court ruled that a valid right of pledge can be established on goods that are delivered subject to retention of title (of ownership). If the buyer is declared bankrupt, the conditional ownership can become an uncondition...




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Secluded Kalkan draws attention of local tourists wanting to holiday in isolation

As coronavirus lockdowns around the world are easing, the resort town of Kalkan on the Mediterranean coast is drawing the attention of tourists who want to holiday in isolation.



  • Arts & Life

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BREXIT – UK REACH – Potential Judicial Review?

Contenders to replace Theresa May as Conservative leader continue to clash over the prospect of a no-deal Brexit and how it could be achieved. In the meantime, the chemicals sector continues to attempt to mitigate the major ramifications it could ha...




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ECHA’s proposal to restrict intentionally added microplastics

The public consultation launched by the European Chemicals Agency (“ECHA”) on the topic of microplastics closed on 20 September 2019 with the submission of 477 comments. The consultation followed the publication by ECHA earlier this year...




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Education Briefing - Coronavirus Job Retention Scheme: Guidance for Employers

1. INTRODUCTION On Friday 20 March 2020, the Chancellor announced a new “Coronavirus Job Retention Scheme” (the Scheme) to help pay people’s wages. Employers will be able to contact HMRC for a grant to cover most of the wages of their workforce who ...




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Education briefing: Coronavirus - New Guidance: Government update on the Coronavirus Job Retention Scheme

On Friday 20 March 2020, the Chancellor announced a new “Coronavirus Job Retention Scheme” (the Scheme) to help pay people’s wages. See our previous briefings of 23 March and Full Article



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Education briefing - Coronavirus - Further guidance on Coronavirus Job Retention Scheme

In previous briefings (here and here and Full Article



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Follow the leader: How COVID-19 could unlock Japan’s giving potential

As celebrities reveal details about their charitable giving during the COVID-19 pandemic, some feel it could be the start of a new attitude to donating ...




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NBA proceeding with extreme caution toward potential restart

The NBA says some players can voluntarily return to their team practice facilities starting Friday, with some very specific conditions and only in places where ...




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Is It Consistent for Continuationists to Affirm the Sufficiency of Scripture?

Have you ever attended a church where public prophecies are allowed, or even encouraged, during the service? Have you heard professing believers claim to have special prophetic insights or words of knowledge directly from God? Such behavior is commonplace in charismatic circles, even in many churches that would verbally affirm the doctrine of the sufficiency of Scripture.

READ MORE




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Israel concerned over US intention to withdraw troops from Sinai

Israel would rather have the United States keeping its 400 soldiers in the Sinai Peninsula, especially on the backdrop of growing tensions there and increased jihadist activity.




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Coronavirus: Two antibodies identified for potential drug treatment by Chinese scientists

Chinese scientists say they have identified two antibodies that could be candidates for a cocktail treatment for patients with different strains of the coronavirus.The antibodies were found to work together as a team to prevent the virus from latching onto a host cell, in a study led by Chinese Centre for Disease Control and Prevention director George Fu Gao with collaborators from across the country.They said that even a mutant strain was likely to be neutralised because the antibodies…




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Enforced Disappearances, Arbitrary Detentions, Hate Speech & Attacks on Civilians – ICC Report on Libya

The International Criminal Court (ICC) on Tuesday highlighted crimes against humanity and grave mismanagement of the law in Libya during a release of their latest report on the North African nation.  Fatou Bensouda, Chief Prosecutor of the ICC, said enforced disappearances, arbitrary detentions, hate speech, and severe maltreatment of detainees remains a massive concern in […]

The post Enforced Disappearances, Arbitrary Detentions, Hate Speech & Attacks on Civilians – ICC Report on Libya appeared first on Inter Press Service.




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Religion & its Discontents: Considerations Around COVID-19 & Africa

Dr. Azza Karam is the Secretary General of Religions for Peace International and Professor of Religion and Development at the Vrije Universiteit (VU), Amsterdam; Dr. Mustafa Y. Ali is the Secretary General of the Global Network of Religions for Children (GNRC) based in Nairobi, Kenya.

The post Religion & its Discontents: Considerations Around COVID-19 & Africa appeared first on Inter Press Service.




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SHC tells home dept to decide banned outfit activist's plea against detention in a week

The Sindh High Court has directed the home department to decide the representation of a proscribed organisation’s activist against his 90 days’ detention under the Maintenance of Public Order within a week.The activist, Abdul Hameed Bugti, had been recently released in the Pakistan...




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Two Years of Unlocking Potential, Performance and Productivity through HARMAN University

By Dr. Cristina Bettencourt, Head of HARMAN University   At HARMAN, we owe every degree of our success to our talented and dedicated employees. While we already have extraordinary talent across all of our operations, we never stop trying to improve by...




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HARMAN Professional Delights Indian Content Creators and ‘Prosumers’ With A Range of Exciting New Products




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HARMAN Showcases Life-Saving Potential of Vehicle-to-Pedestrian 5G Technology at CES 2020

CES 2020 – LAS VEGAS, Nev. – January 6, 2020 – HARMAN, a wholly-owned subsidiary of Samsung Electronics Co., Ltd., focused on connected technologies and solutions for automotive, consumer and enterprise markets, today unveiled a new ADAS use case, called...




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BCG vaccine being trialled as potential protection against covid-19

A long-standing hypothesis suggests the BCG vaccine also serves to generally enhance the immune system, meaning it could protect against covid-19, and trials are under way to find out




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Facebook names first members of content oversight board

Facebook's new content oversight board will include a former prime minister, a Nobel Peace Prize laureate and several constitutional law experts and rights advocates in its first 20 members.




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Facebook names first members of content oversight board

Facebook's new content oversight board will include a former prime minister, a Nobel Peace Prize laureate and several constitutional law experts and rights advocates in its first 20 members.




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AHA News: Persistent Asthma Linked to Increased Risk for Heart Rhythm Disorder

Title: AHA News: Persistent Asthma Linked to Increased Risk for Heart Rhythm Disorder
Category: Health News
Created: 2/4/2020 12:00:00 AM
Last Editorial Review: 2/5/2020 12:00:00 AM




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Test Spots Potential Organ Donors Among Coma Patients

Title: Test Spots Potential Organ Donors Among Coma Patients
Category: Health News
Created: 4/26/2010 4:10:00 PM
Last Editorial Review: 4/27/2010 12:00:00 AM




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Low Testosterone Raises Heart Death Rates in Impotent Men

Title: Low Testosterone Raises Heart Death Rates in Impotent Men
Category: Health News
Created: 4/29/2010 2:10:00 PM
Last Editorial Review: 4/30/2010 12:00:00 AM




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Blood Clot Risk for Outpatients Needs More Attention: Study

Title: Blood Clot Risk for Outpatients Needs More Attention: Study
Category: Health News
Created: 4/27/2012 4:05:00 PM
Last Editorial Review: 4/30/2012 12:00:00 AM




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Legal Pot Products Too Potent for Chronic Pain

Title: Legal Pot Products Too Potent for Chronic Pain
Category: Health News
Created: 3/27/2020 12:00:00 AM
Last Editorial Review: 3/27/2020 12:00:00 AM




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PMC Now Offers a “Preview” Table of Contents for Embargoed Issues

For any journal issue that has at least one open access or early access article, PMC is now displaying the table of contents (TOC) in advance of the whole issue becoming available. Not to worry, though—only those articles specified for early release are immediately viewable in PMC. As consistent with the terms of access in the journal agreement, the other articles will only become available on their specified release date, as shown in the TOC below.

The journal's accessiblity, as indicated on the PMC Journal list also has not changed; for example, Plant Physiology's embargo period is still 12 months. What has changed is that the issues with “preview” TOCs now additionally appear on the journal's archive page. Publishers and others can rest assured, however, that no access terms for any journal have been changed with the unveiling of this new format.




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lopinavir and ritonavir (Kaletra): Potential COVID-19 Drug

Title: lopinavir and ritonavir (Kaletra): Potential COVID-19 Drug
Category: Medications
Created: 3/12/2001 12:00:00 AM
Last Editorial Review: 4/8/2020 12:00:00 AM




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azithromycin (Zithromax): Potential COVID-19 Combo Drug

Title: azithromycin (Zithromax): Potential COVID-19 Combo Drug
Category: Medications
Created: 12/31/1997 12:00:00 AM
Last Editorial Review: 3/30/2020 12:00:00 AM




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A Consistent Bedtime Is Good for Your Heart

Title: A Consistent Bedtime Is Good for Your Heart
Category: Health News
Created: 4/3/2020 12:00:00 AM
Last Editorial Review: 4/6/2020 12:00:00 AM




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Pharmacologic Inhibitor of DNA-PK, M3814, Potentiates Radiotherapy and Regresses Human Tumors in Mouse Models

Physical and chemical DNA-damaging agents are used widely in the treatment of cancer. Double-strand break (DSB) lesions in DNA are the most deleterious form of damage and, if left unrepaired, can effectively kill cancer cells. DNA-dependent protein kinase (DNA-PK) is a critical component of nonhomologous end joining (NHEJ), one of the two major pathways for DSB repair. Although DNA-PK has been considered an attractive target for cancer therapy, the development of pharmacologic DNA-PK inhibitors for clinical use has been lagging. Here, we report the discovery and characterization of a potent, selective, and orally bioavailable DNA-PK inhibitor, M3814 (peposertib), and provide in vivo proof of principle for DNA-PK inhibition as a novel approach to combination radiotherapy. M3814 potently inhibits DNA-PK catalytic activity and sensitizes multiple cancer cell lines to ionizing radiation (IR) and DSB-inducing agents. Inhibition of DNA-PK autophosphorylation in cancer cells or xenograft tumors led to an increased number of persistent DSBs. Oral administration of M3814 to two xenograft models of human cancer, using a clinically established 6-week fractionated radiation schedule, strongly potentiated the antitumor activity of IR and led to complete tumor regression at nontoxic doses. Our results strongly support DNA-PK inhibition as a novel approach for the combination radiotherapy of cancer. M3814 is currently under investigation in combination with radiotherapy in clinical trials.




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Mycobacterium tuberculosis Reactivates HIV-1 via Exosome-Mediated Resetting of Cellular Redox Potential and Bioenergetics

ABSTRACT

The synergy between Mycobacterium tuberculosis and human immunodeficiency virus-1 (HIV-1) interferes with therapy and facilitates the pathogenesis of both human pathogens. Fundamental mechanisms by which M. tuberculosis exacerbates HIV-1 infection are not clear. Here, we show that exosomes secreted by macrophages infected with M. tuberculosis, including drug-resistant clinical strains, reactivated HIV-1 by inducing oxidative stress. Mechanistically, M. tuberculosis-specific exosomes realigned mitochondrial and nonmitochondrial oxygen consumption rates (OCR) and modulated the expression of host genes mediating oxidative stress response, inflammation, and HIV-1 transactivation. Proteomics analyses revealed the enrichment of several host factors (e.g., HIF-1α, galectins, and Hsp90) known to promote HIV-1 reactivation in M. tuberculosis-specific exosomes. Treatment with a known antioxidant—N-acetyl cysteine (NAC)—or with inhibitors of host factors—galectins and Hsp90—attenuated HIV-1 reactivation by M. tuberculosis-specific exosomes. Our findings uncover new paradigms for understanding the redox and bioenergetics bases of HIV-M. tuberculosis coinfection, which will enable the design of effective therapeutic strategies.

IMPORTANCE Globally, individuals coinfected with the AIDS virus (HIV-1) and with M. tuberculosis (causative agent of tuberculosis [TB]) pose major obstacles in the clinical management of both diseases. At the heart of this issue is the apparent synergy between the two human pathogens. On the one hand, mechanisms induced by HIV-1 for reactivation of TB in AIDS patients are well characterized. On the other hand, while clinical findings clearly identified TB as a risk factor for HIV-1 reactivation and associated mortality, basic mechanisms by which M. tuberculosis exacerbates HIV-1 replication and infection remain poorly characterized. The significance of our research is in identifying the role of fundamental mechanisms such as redox and energy metabolism in catalyzing HIV-M. tuberculosis synergy. The quantification of redox and respiratory parameters affected by M. tuberculosis in stimulating HIV-1 will greatly enhance our understanding of HIV-M. tuberculosis coinfection, leading to a wider impact on the biomedical research community and creating new translational opportunities.




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Defining Stage-Specific Activity of Potent New Inhibitors of Cryptosporidium parvum Growth In Vitro

ABSTRACT

Cryptosporidium parvum and Cryptosporidium hominis have emerged as major enteric pathogens of infants in the developing world, in addition to their known importance in immunocompromised adults. Although there has been recent progress in identifying new small molecules that inhibit Cryptosporidium sp. growth in vitro or in animal models, we lack information about their mechanism of action, potency across the life cycle, and cidal versus static activities. Here, we explored four potent classes of compounds that include inhibitors that likely target phosphatidylinositol 4 kinase (PI4K), phenylalanine-tRNA synthetase (PheRS), and several potent inhibitors with unknown mechanisms of action. We utilized monoclonal antibodies and gene expression probes for staging life cycle development to define the timing of when inhibitors were active during the life cycle of Cryptosporidium parvum grown in vitro. These different classes of inhibitors targeted different stages of the life cycle, including compounds that blocked replication (PheRS inhibitors), prevented the segmentation of daughter cells and thus blocked egress (PI4K inhibitors), or affected sexual-stage development (a piperazine compound of unknown mechanism). Long-term cultivation of C. parvum in epithelial cell monolayers derived from intestinal stem cells was used to distinguish between cidal and static activities based on the ability of parasites to recover from treatment. Collectively, these approaches should aid in identifying mechanisms of action and for designing in vivo efficacy studies based on time-dependent concentrations needed to achieve cidal activity.

IMPORTANCE Currently, nitazoxanide is the only FDA-approved treatment for cryptosporidiosis; unfortunately, it is ineffective in immunocompromised patients, has varied efficacy in immunocompetent individuals, and is not approved in infants under 1 year of age. Identifying new inhibitors for the treatment of cryptosporidiosis requires standardized and quantifiable in vitro assays for assessing potency, selectivity, timing of activity, and reversibility. Here, we provide new protocols for defining which stages of the life cycle are susceptible to four highly active compound classes that likely inhibit different targets in the parasite. We also utilize a newly developed long-term culture system to define assays for monitoring reversibility as a means of defining cidal activity as a function of concentration and time of treatment. These assays should provide valuable in vitro parameters to establish conditions for efficacious in vivo treatment.




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Latent Toxoplasmosis Effects on Rodents and Humans: How Much is Real and How Much is Media Hype?

ABSTRACT

Toxoplasma gondii is a ubiquitous, intracellular protozoan parasite with a broad range of intermediate hosts, including humans and rodents. In many hosts, T. gondii establishes a latent long-term infection by converting from its rapidly dividing or lytic form to its slowly replicating and encysting form. In humans and rodents, the major organ for encystment is the central nervous system (CNS), which has led many to investigate how this persistent CNS infection might influence rodent and human behavior and, more recently, neurodegenerative diseases. Given the interest in this topic, here we seek to take a global approach to the data for and against the effects of latent T. gondii on behavior and neurodegeneration and the proposed mechanisms that might underlie behavior modifications.




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A Solution to Antifolate Resistance in Group B Streptococcus: Untargeted Metabolomics Identifies Human Milk Oligosaccharide-Induced Perturbations That Result in Potentiation of Trimethoprim

ABSTRACT

Adjuvants can be used to potentiate the function of antibiotics whose efficacy has been reduced by acquired or intrinsic resistance. In the present study, we discovered that human milk oligosaccharides (HMOs) sensitize strains of group B Streptococcus (GBS) to trimethoprim (TMP), an antibiotic to which GBS is intrinsically resistant. Reductions in the MIC of TMP reached as high as 512-fold across a diverse panel of isolates. To better understand HMOs’ mechanism of action, we characterized the metabolic response of GBS to HMO treatment using ultrahigh-performance liquid chromatography–high-resolution tandem mass spectrometry (UPLC-HRMS/MS) analysis. These data showed that when challenged by HMOs, GBS undergoes significant perturbations in metabolic pathways related to the biosynthesis and incorporation of macromolecules involved in membrane construction. This study represents reports the metabolic characterization of a cell that is perturbed by HMOs.

IMPORTANCE Group B Streptococcus is an important human pathogen that causes serious infections during pregnancy which can lead to chorioamnionitis, funisitis, premature rupture of gestational membranes, preterm birth, neonatal sepsis, and death. GBS is evolving antimicrobial resistance mechanisms, and the work presented in this paper provides evidence that prebiotics such as human milk oligosaccharides can act as adjuvants to restore the utility of antibiotics.




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Localized Hypermutation is the Major Driver of Meningococcal Genetic Variability during Persistent Asymptomatic Carriage

ABSTRACT

Host persistence of bacteria is facilitated by mutational and recombinatorial processes that counteract loss of genetic variation during transmission and selection from evolving host responses. Genetic variation was investigated during persistent asymptomatic carriage of Neisseria meningitidis. Interrogation of whole-genome sequences for paired isolates from 25 carriers showed that de novo mutations were infrequent, while horizontal gene transfer occurred in 16% of carriers. Examination of multiple isolates per time point enabled separation of sporadic and transient allelic variation from directional variation. A comprehensive comparative analysis of directional allelic variation with hypermutation of simple sequence repeats and hyperrecombination of class 1 type IV pilus genes detected an average of seven events per carrier and 2:1 bias for changes due to localized hypermutation. Directional genetic variation was focused on the outer membrane with 69% of events occurring in genes encoding enzymatic modifiers of surface structures or outer membrane proteins. Multiple carriers exhibited directional and opposed switching of allelic variants of the surface-located Opa proteins that enables continuous expression of these adhesins alongside antigenic variation. A trend for switching from PilC1 to PilC2 expression was detected, indicating selection for specific alterations in the activities of the type IV pilus, whereas phase variation of restriction modification (RM) systems, as well as associated phasevarions, was infrequent. We conclude that asymptomatic meningococcal carriage on mucosal surfaces is facilitated by frequent localized hypermutation and horizontal gene transfer affecting genes encoding surface modifiers such that optimization of adhesive functions occurs alongside escape of immune responses by antigenic variation.

IMPORTANCE Many bacterial pathogens coexist with host organisms, rarely causing disease while adapting to host responses. Neisseria meningitidis, a major cause of meningitis and septicemia, is a frequent persistent colonizer of asymptomatic teenagers/young adults. To assess how genetic variation contributes to host persistence, whole-genome sequencing and hypermutable sequence analyses were performed on multiple isolates obtained from students naturally colonized with meningococci. High frequencies of gene transfer were observed, occurring in 16% of carriers and affecting 51% of all nonhypermutable variable genes. Comparative analyses showed that hypermutable sequences were the major mechanism of variation, causing 2-fold more changes in gene function than other mechanisms. Genetic variation was focused on genes affecting the outer membrane, with directional changes in proteins responsible for bacterial adhesion to host surfaces. This comprehensive examination of genetic plasticity in individual hosts provides a significant new platform for rationale design of approaches to prevent the spread of this pathogen.




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Avoiding Drug Resistance by Substrate Envelope-Guided Design: Toward Potent and Robust HCV NS3/4A Protease Inhibitors

ABSTRACT

Hepatitis C virus (HCV) infects millions of people worldwide, causing chronic liver disease that can lead to cirrhosis, hepatocellular carcinoma, and liver transplant. In the last several years, the advent of direct-acting antivirals, including NS3/4A protease inhibitors (PIs), has remarkably improved treatment outcomes of HCV-infected patients. However, selection of resistance-associated substitutions and polymorphisms among genotypes can lead to drug resistance and in some cases treatment failure. A proactive strategy to combat resistance is to constrain PIs within evolutionarily conserved regions in the protease active site. Designing PIs using the substrate envelope is a rational strategy to decrease the susceptibility to resistance by using the constraints of substrate recognition. We successfully designed two series of HCV NS3/4A PIs to leverage unexploited areas in the substrate envelope to improve potency, specifically against resistance-associated substitutions at D168. Our design strategy achieved better resistance profiles over both the FDA-approved NS3/4A PI grazoprevir and the parent compound against the clinically relevant D168A substitution. Crystallographic structural analysis and inhibition assays confirmed that optimally filling the substrate envelope is critical to improve inhibitor potency while avoiding resistance. Specifically, inhibitors that enhanced hydrophobic packing in the S4 pocket and avoided an energetically frustrated pocket performed the best. Thus, the HCV substrate envelope proved to be a powerful tool to design robust PIs, offering a strategy that can be translated to other targets for rational design of inhibitors with improved potency and resistance profiles.

IMPORTANCE Despite significant progress, hepatitis C virus (HCV) continues to be a major health problem with millions of people infected worldwide and thousands dying annually due to resulting complications. Recent antiviral combinations can achieve >95% cure, but late diagnosis, low access to treatment, and treatment failure due to drug resistance continue to be roadblocks against eradication of the virus. We report the rational design of two series of HCV NS3/4A protease inhibitors with improved resistance profiles by exploiting evolutionarily constrained regions of the active site using the substrate envelope model. Optimally filling the S4 pocket is critical to avoid resistance and improve potency. Our results provide drug design strategies to avoid resistance that are applicable to other quickly evolving viral drug targets.




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Advances in Understanding the Human Urinary Microbiome and Its Potential Role in Urinary Tract Infection

ABSTRACT

Recent advances in the analysis of microbial communities colonizing the human body have identified a resident microbial community in the human urinary tract (UT). Compared to many other microbial niches, the human UT harbors a relatively low biomass. Studies have identified many genera and species that may constitute a core urinary microbiome. However, the contribution of the UT microbiome to urinary tract infection (UTI) and recurrent UTI (rUTI) pathobiology is not yet clearly understood. Evidence suggests that commensal species within the UT and urogenital tract (UGT) microbiomes, such as Lactobacillus crispatus, may act to protect against colonization with uropathogens. However, the mechanisms and fundamental biology of the urinary microbiome-host relationship are not understood. The ability to measure and characterize the urinary microbiome has been enabled through the development of next-generation sequencing and bioinformatic platforms that allow for the unbiased detection of resident microbial DNA. Translating technological advances into clinical insight will require further study of the microbial and genomic ecology of the urinary microbiome in both health and disease. Future diagnostic, prognostic, and therapeutic options for the management of UTI may soon incorporate efforts to measure, restore, and/or preserve the native, healthy ecology of the urinary microbiomes.




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Pseudorabies Virus Infection of Epithelial Cells Leads to Persistent but Aberrant Activation of the NF-{kappa}B Pathway, Inhibiting Hallmark NF-{kappa}B-Induced Proinflammatory Gene Expression [Virus-Cell Interactions]

The nuclear factor kappa B (NF-B) is a potent transcription factor, activation of which typically results in robust proinflammatory signaling and triggering of fast negative feedback modulators to avoid excessive inflammatory responses. Here, we report that infection of epithelial cells, including primary porcine respiratory epithelial cells, with the porcine alphaherpesvirus pseudorabies virus (PRV) results in the gradual and persistent activation of NF-B, illustrated by proteasome-dependent degradation of the inhibitory NF-B regulator IB and nuclear translocation and phosphorylation of the NF-B subunit p65. PRV-induced persistent activation of NF-B does not result in expression of negative feedback loop genes, like the gene for IBα or A20, and does not trigger expression of prototypical proinflammatory genes, like the gene for tumor necrosis factor alpha (TNF-α) or interleukin-6 (IL-6). In addition, PRV infection inhibits TNF-α-induced canonical NF-B activation. Hence, PRV infection triggers persistent NF-B activation in an unorthodox way and dramatically modulates the NF-B signaling axis, preventing typical proinflammatory gene expression and the responsiveness of cells to canonical NF-B signaling, which may aid the virus in modulating early proinflammatory responses in the infected host.

IMPORTANCE The NF-B transcription factor is activated via different key inflammatory pathways and typically results in the fast expression of several proinflammatory genes as well as negative feedback loop genes to prevent excessive inflammation. In the current report, we describe that infection of cells with the porcine alphaherpesvirus pseudorabies virus (PRV) triggers a gradual and persistent aberrant activation of NF-B, which does not result in expression of hallmark proinflammatory or negative feedback loop genes. In addition, although PRV-induced NF-B activation shares some mechanistic features with canonical NF-B activation, it also shows remarkable differences; e.g., it is largely independent of the canonical IB kinase (IKK) and even renders infected cells resistant to canonical NF-B activation by the inflammatory cytokine TNF-α. Aberrant PRV-induced NF-B activation may therefore paradoxically serve as a viral immune evasion strategy and may represent an important tool to unravel currently unknown mechanisms and consequences of NF-B activation.




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Priming of Antiviral CD8 T Cells without Effector Function by a Persistently Replicating Hepatitis C-Like Virus [Pathogenesis and Immunity]

Immune-competent animal models for the hepatitis C virus (HCV) are nonexistent, impeding studies of host-virus interactions and vaccine development. Experimental infection of laboratory rats with a rodent hepacivirus isolated from Rattus norvegicus (RHV) is a promising surrogate model due to its recapitulation of HCV-like chronicity. However, several aspects of rat RHV infection remain unclear, for instance, how RHV evades host adaptive immunity to establish persistent infection. Here, we analyzed the induction, differentiation, and functionality of RHV-specific CD8 T cell responses that are essential for protection against viral persistence. Virus-specific CD8 T cells targeting dominant and subdominant major histocompatibility complex class I epitopes proliferated considerably in liver after RHV infection. These populations endured long term yet never acquired antiviral effector functions or selected for viral escape mutations. This was accompanied by the persistent upregulation of programmed cell death-1 and absent memory cell formation, consistent with a dysfunctional phenotype. Remarkably, transient suppression of RHV viremia with a direct-acting antiviral led to the priming of CD8 T cells with partial effector function, driving the selection of a viral escape variant. These data demonstrate an intrinsic abnormality within CD8 T cells primed by rat RHV infection, an effect that is governed at least partially by the magnitude of early virus replication. Thus, this model could be useful in investigating mechanisms of CD8 T cell subversion, leading to the persistence of hepatotropic pathogens such as HCV.

IMPORTANCE Development of vaccines against hepatitis C virus (HCV), a major cause of cirrhosis and cancer, has been stymied by a lack of animal models. The recent discovery of an HCV-like rodent hepacivirus (RHV) enabled the development of such a model in rats. This platform recapitulates HCV hepatotropism and viral chronicity necessary for vaccine testing. Currently, there are few descriptions of RHV-specific responses and why they fail to prevent persistent infection in this model. Here, we show that RHV-specific CD8 T cells, while induced early at high magnitude, do not develop into functional effectors capable of controlling virus. This defect was partially alleviated by short-term treatment with an HCV antiviral. Thus, like HCV, RHV triggers dysfunction of virus-specific CD8 T cells that are vital for infection resolution. Additional study of this evasion strategy and how to mitigate it could enhance our understanding of hepatotropic viral infections and lead to improved vaccines and therapeutics.




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Extent of Fermi-surface reconstruction in the high-temperature superconductor HgBa2CuO4+{delta} [Physics]

High magnetic fields have revealed a surprisingly small Fermi surface in underdoped cuprates, possibly resulting from Fermi-surface reconstruction due to an order parameter that breaks translational symmetry of the crystal lattice. A crucial issue concerns the doping extent of such a state and its relationship to the principal pseudogap and...




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The effect of vertical extent of stimuli on cockroach optomotor response [RESEARCH ARTICLE]

Juha Nuutila, Anna E. Honkanen, Kyösti Heimonen, and Matti Weckström

Using tethered American cockroaches walking on a trackball in a spherical virtual reality environment, we tested optomotor responses to horizontally moving black-and-white gratings of different vertical extent under six different light intensities. We found that shortening the vertical extent of the wide-field stimulus grating within a light level weakened response strength, reduced average velocity, and decreased angular walking distance. Optomotor responses with the vertically shortened stimuli persisted down to light intensity levels of 0.05 lx. Response latency seems to be independent of both the height of the stimulus and light intensity. The optomotor response started saturating at the light intensity of 5 lx, where the shortest behaviourally significant stimulus was 1°. This indicates that the number of vertical ommatidial rows needed to elicit an optomotor response at 5 lx and above is in the single digits, maybe even just one. Our behavioural results encourage further inquiry into the interplay of light intensity and stimulus size in insect dim-light vision.




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Use of Human Induced Pluripotent Stem Cells and Kidney Organoids To Develop a Cysteamine/mTOR Inhibition Combination Therapy for Cystinosis

Background

Mutations in CTNS—a gene encoding the cystine transporter cystinosin—cause the rare, autosomal, recessive, lysosomal-storage disease cystinosis. Research has also implicated cystinosin in modulating the mTORC1 pathway, which serves as a core regulator of cellular metabolism, proliferation, survival, and autophagy. In its severest form, cystinosis is characterized by cystine accumulation, renal proximal tubule dysfunction, and kidney failure. Because treatment with the cystine-depleting drug cysteamine only slows disease progression, there is an urgent need for better treatments.

Methods

To address a lack of good human-based cell culture models for studying cystinosis, we generated the first human induced pluripotent stem cell (iPSC) and kidney organoid models of the disorder. We used a variety of techniques to examine hallmarks of cystinosis—including cystine accumulation, lysosome size, the autophagy pathway, and apoptosis—and performed RNA sequencing on isogenic lines to identify differentially expressed genes in the cystinosis models compared with controls.

Results

Compared with controls, these cystinosis models exhibit elevated cystine levels, increased apoptosis, and defective basal autophagy. Cysteamine treatment ameliorates this phenotype, except for abnormalities in apoptosis and basal autophagy. We found that treatment with everolimus, an inhibitor of the mTOR pathway, reduces the number of large lysosomes, decreases apoptosis, and activates autophagy, but it does not rescue the defect in cystine loading. However, dual treatment of cystinotic iPSCs or kidney organoids with cysteamine and everolimus corrects all of the observed phenotypic abnormalities.

Conclusions

These observations suggest that combination therapy with a cystine-depleting drug such as cysteamine and an mTOR pathway inhibitor such as everolimus has potential to improve treatment of cystinosis.




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In Vivo Assessment of Size-Selective Glomerular Sieving in Transplanted Human Induced Pluripotent Stem Cell-Derived Kidney Organoids

Background

The utility of kidney organoids in regenerative medicine will rely on the functionality of the glomerular and tubular structures in these tissues. Recent studies have demonstrated the vascularization and subsequent maturation of human pluripotent stem cell–derived kidney organoids after renal subcapsular transplantation. This raises the question of whether the glomeruli also become functional upon transplantation.

Methods

We transplanted kidney organoids under the renal capsule of the left kidney in immunodeficient mice followed by the implantation of a titanium imaging window on top of the kidney organoid. To assess glomerular function in the transplanted human pluripotent stem cell–derived kidney tissue 1, 2, and 3 weeks after transplantation, we applied high-resolution intravital multiphoton imaging through the imaging window during intravenous infusion of fluorescently labeled low and high molecular mass dextran molecules or albumin.

Results

After vascularization, glomerular structures in the organoid displayed dextran and albumin size selectivity across their glomerular filtration barrier. We also observed evidence of proximal tubular dextran reuptake.

Conclusions

Our results demonstrate that human pluripotent stem cell–derived glomeruli can develop an appropriate barrier function and discriminate between molecules of varying size. These characteristics together with tubular presence of low molecular mass dextran provide clear evidence of functional filtration. This approach to visualizing glomerular filtration function will be instrumental for translation of organoid technology for clinical applications as well as for disease modeling.




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Axon microdissection and transcriptome profiling reveals the in vivo RNA content of fully differentiated myelinated motor axons [ARTICLE]

Axonal protein synthesis has been shown to play a role in developmental and regenerative growth, as well as in the maintenance of the axoplasm in a steady state. Recent studies have begun to identify the mRNAs localized in axons, which could be translated locally under different conditions. Despite that by now hundreds or thousands of mRNAs have been shown to be localized into the axonal compartment of cultured neurons in vitro, knowledge of which mRNAs are localized in mature myelinated axons is quite limited. With the purpose of characterizing the transcriptome of mature myelinated motor axons of peripheral nervous systems, we modified the axon microdissection method devised by Koenig, enabling the isolation of the axoplasm RNA to perform RNA-seq analysis. The transcriptome analysis indicates that the number of RNAs detected in mature axons is lower in comparison with in vitro data, depleted of glial markers, and enriched in neuronal markers. The mature myelinated axons are enriched for mRNAs related to cytoskeleton, translation, and oxidative phosphorylation. Moreover, it was possible to define core genes present in axons when comparing our data with transcriptomic data of axons grown in different conditions. This work provides evidence that axon microdissection is a valuable method to obtain genome-wide data from mature and myelinated axons of the peripheral nervous system, and could be especially useful for the study of axonal involvement in neurodegenerative pathologies of motor neurons such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophies (SMA).




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{alpha}-Synuclein filaments from transgenic mouse and human synucleinopathy-containing brains are maȷor seed-competent species [Molecular Bases of Disease]

Assembled α-synuclein in nerve cells and glial cells is the defining pathological feature of neurodegenerative diseases called synucleinopathies. Seeds of α-synuclein can induce the assembly of monomeric protein. Here, we used sucrose gradient centrifugation and transiently transfected HEK 293T cells to identify the species of α-synuclein from the brains of homozygous, symptomatic mice transgenic for human mutant A53T α-synuclein (line M83) that seed aggregation. The most potent fractions contained Sarkosyl-insoluble assemblies enriched in filaments. We also analyzed six cases of idiopathic Parkinson's disease (PD), one case of familial PD, and six cases of multiple system atrophy (MSA) for their ability to induce α-synuclein aggregation. The MSA samples were more potent than those of idiopathic PD in seeding aggregation. We found that following sucrose gradient centrifugation, the most seed-competent fractions from PD and MSA brains are those that contain Sarkosyl-insoluble α-synuclein. The fractions differed between PD and MSA, consistent with the presence of distinct conformers of assembled α-synuclein in these different samples. We conclude that α-synuclein filaments are the main driving force for amplification and propagation of pathology in synucleinopathies.