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Protesters want Alberta to reopen economy more quickly

Dozens of protesters descended on the legislature Saturday afternoon, calling for a quicker reopening of the Alberta economy.




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Special event helps children of single mom's show their appreciation

Some kids took advantage of the opportunity to show their appreciation for their moms on Saturday afternoon at the Love You Mama event.




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Goodwill donation centres reopen, need for donations on the rise in Alberta

There was a steady stream of people dropping off donations at Goodwill’s donation centres Saturday—marking the first day it was open in about six weeks.




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Kiwanis and Soap for Hope lend a (clean) helping hand

A new, squeaky clean business venture is helping Calgary’s most vulnerable during the COVID-19 pandemic.




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Sport24.co.za | Stewart prepared for first county cricket wipeout since WWII

Surrey director of cricket Alec Stewart has reluctantly accepted there could yet be a long-term good for the county game if it is wiped out in 2020.




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Sport24.co.za | Hearts owner laments 'disrespect' of her task force

Scottish football descended into fresh acrimony when Hearts owner Ann Budge accused her Premiership counterparts of "appalling disrespect".




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Sport24.co.za | Rabiot 'open' to Premier League transfer

Manchester United and Everton have been put on alert by the news that Juventus midfielder Adrien Rabiot is willing to move to the Premier League.




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Sport24.co.za | Modiba: I stayed because SuperSport made me feel appreciated

SuperSport United winger Aubrey Modiba says a conversation with club CEO Stanley Matthews convinced him to stay despite interest from Mamelodi Sundowns.




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Sport24.co.za | Lions legend says they need a confrontational skipper against Springboks: 'That is their DNA'

Former captain Paul O'Connell says it will be vital for the British & Irish Lions to pick a leader capable of beating the Springboks at their own game.




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Skipper Butterfly


A Skipper Butterfly, photographed today in my backyard in Bendigo, Victoria.




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Sharp-tailed Sandpiper


I photographed this Sharp-tailed Sandpiper (Calidris acuminata) today near Stanhope in Victoria.









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'Of course, I'm worried': PM Trudeau expresses concern about Quebec's reopening plans

As Quebec begins to reopen schools and businesses, Prime Minister Justin Trudeau said he’s ‘worried’ about the province’s deconfinement plans, particularly in Montreal.




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No throwing rice or extra guests permitted – but you can have a COVID-19 'micro-wedding' at Vancouver city hall

The city says couples can book its Helena Gutteridge Plaza at City Hall for just $85 and bring eight guests to have an outdoor, physically distant wedding ceremony.




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101-year-old retailer Army & Navy will close permanently, says owner

A department store that served Vancouver's Gastown and Downtown Eastside neighbourhoods for decades is closing, along with four other Army and Navy locations, because of the COVID-19 pandemic.




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Haircuts could be more expensive when salons reopen because of added costs

The manager of a Vancouver barber shop warns that once many B.C. salons are back open, they may have to implement a price increase for their services.




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Last camper moves out of Oppenheimer Park as cleanup begins

Police and City of Vancouver park rangers escorted the last person living in Oppenheimer Park out of the tent city Saturday afternoon, moments before crews with excavators moved in to clean up the mountains of trash left behind.




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California Sheriff Refuses to Arrest People Defying Stay-at-Home Order: “There cannot be a new normal”

The following article, California Sheriff Refuses to Arrest People Defying Stay-at-Home Order: “There cannot be a new normal”, was first published on 100PercentFedUp.com.

Riverside, California Sheriff Chad Bianco spoke to the Riverside Board of Supervisors on May 5th to say that he will not enforce the stay-at-home order in California. He tells people who are afraid of contracting the coronavirus that they should stay home if they want to. Bianco continues with the suggestion that any business owner […]

Continue reading: California Sheriff Refuses to Arrest People Defying Stay-at-Home Order: “There cannot be a new normal” ...




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Witness Tampering? Asst. HHS Secretary Releases Threatening Text Messages From Dem Rep. Eric Swalwell: “In clear violation of House Ethics rules “

The following article, Witness Tampering? Asst. HHS Secretary Releases Threatening Text Messages From Dem Rep. Eric Swalwell: “In clear violation of House Ethics rules “, was first published on 100PercentFedUp.com.

Now that Michael Caputo, who was previously a target of the Mueller investigation, has been cleared, he has released some pretty damning text messages from the virulently anti-Trump lawmaker from California, Rep. Eric Swalwell (D). The text messages appear to prove that Swalwell, who has spent the last 3 1/2 years calling for Trump’s impeachment, […]

Continue reading: Witness Tampering? Asst. HHS Secretary Releases Threatening Text Messages From Dem Rep. Eric Swalwell: “In clear violation of House Ethics rules “ ...




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Global Attitudes: Perspectives on the US-China Power Shift

Members Event

15 July 2014 - 1:00pm to 2:00pm

Chatham House, London

Event participants

Bruce Stokes, Director, Global Economic Attitudes project, Pew Research Center; Associate Fellow, Americas Programme, Chatham House
Roderic Wye, Associate Fellow, Asia Programme, Chatham House
Dr Alexandra de Hoop Scheffer, Senior Transatlantic Fellow and Director, Paris Office, German Marshall Fund of the United States 
Chair: Dr Robin Niblett, Director, Chatham House 

With China’s economic power on the rise, there is a growing sense among many publics around the world that the global balance of power is shifting and that China already is, or will soon be, the world’s leading power, according to a new survey. The Pew Research Center’s latest Global Attitudes survey found that despite China’s rise in economic power, the People’s Republic is not very popular in Asia, Europe and the United States. As for the US, although the ‘Obama Bounce’ effect of more positive attitudes toward the United States is waning in Europe and China, anti-Americanism in most countries remains much lower than it was during the Bush administration, but remaining consistent in the Middle East. 

Bruce Stokes will present these findings and the expert panel will discuss the insights it provides into an emerging superpower rivalry. In addition they will discuss how these nuances in global attitudes might increasingly shape the security and economic policies of governments around the world.

Members Events Team




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Angola as a Global Influence: Priorities for International Cooperation

Research Event

13 June 2014 - 3:30pm to 4:30pm

Chatham House, London

Event participants

Dr Maria Ângela Bragança, Secretary of State for Cooperation, Ministry of External Relations, Angola

Reaping the benefits of more than a decade of stability and fast economic growth, Angola increasingly wields global influence. Angola seeks to diversify its bilateral partnerships and improve existing ones, and is well-placed to exert its influence in multilateral fora. 

At this roundtable event, Angola’s Secretary of State for Cooperation, Hon Dr Maria Angela Bragança, will discuss Angola’s international priorities and how Angola is helping to shape key issues of global importance in a multipolar world.

Department/project

Christopher Vandome

Research Fellow, Africa Programme
+44 (0) 20 7314 3669




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Nigeria’s Priorities for Progress: Imperatives for Stability and Inclusive Growth

Research Event

24 July 2014 - 2:30pm to 3:30pm

Chatham House, London

Event participants

Dr Doyin Okupe, Senior Special Assistant on Public Affairs to the President of Nigeria 

Nigeria’s prospects, with its rise to international prominence as Africa’s largest economy, are tempered by the many development and security challenges the country faces. While essential reforms in the power and agriculture sectors are underway, such efforts are balanced against the Boko Haram insurgency in the northeast, significant concerns around youth unemployment, and an increasingly contentious political environment in the run-up to the February 2015 elections. 

Dr Doyin Okupe, Senior Special Assistant to President Goodluck Jonathan, will discuss what steps the presidency is taking to address the country’s most urgent challenges, and how the political environment can be managed to overcome tensions that may impede progress.

Department/project

Christopher Vandome

Research Fellow, Africa Programme
+44 (0) 20 7314 3669




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Peace and Cooperation in Northeast Asia

Invitation Only Research Event

6 October 2014 - 8:30am to 7 October 2014 - 1:45pm

Seoul, Republic of Korea

The overarching theme of this event will be Korea’s changing role as a global power and its effect on the country’s relationships, including with the UK and Europe. It will aim to raise awareness of these issues to an audience of key decision-makers, and to encourage experts to think together strategically about areas of mutual interest, as well as practical ways to achieve deeper cooperation. 

Attendance at this event is by invitation only.

This event is held in partnership with the South Korean newspaper JoongAng Ilbo.

Event attributes

External event

Joshua Webb

+44 (0)20 7314 3678




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Assessing the danger of war: parallels and differences between Europe in 1914 and East Asia in 2014

12 November 2014 , Volume 90, Number 6

Joachim Krause




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India Under Modi: A Superpower in the Making?

Members Event

30 June 2016 - 1:00pm to 2:00pm

Chatham House London, UK

Event participants

Dr Mukulika Banerjee, Director, South Asia Centre, London School of Economics
Nandan Nilekani, Co-founder and Chairman, EkStep; Chairman, Unique Identification Authority of India (UIAI) (2009-14)
Dr Gareth Price, Senior Research Fellow, Asia Programme, Chatham House
Mihir Swarup Sharma, India Columnist, Bloomberg View; Senior Fellow, Observer Research Foundation, New Delhi
Chair: James Crabtree, Contributing Editor, Financial Times; Senior Visiting Fellow, Lee Kuan Yew School of Public Policy

On the surface, the Indian economy is performing well, and the popularity of Narendra Modi, the prime minister elected on the promise of liberalizing reform two years ago, is holding up. Christine Lagarde, the managing director of the International Monetary Fund (IMF), has referred to India as a ‘bright spot’ in the slowing global economy. According to them, growth equalled China’s last year at 7.3% and has now taken the lead as the world’s fastest growing economy. Yet some joke that India’s prospects look brighter the farther away you are.

The panel will reflect on Modi’s two years in power and discuss what they think the government got wrong and what they got right. They will question whether India’s resurgence can be sustained into the future, and discuss what this actually means for the prospects of India’s 1.3 billion people, as well as the balance of power in Asia and beyond.

This event is organized in association with the Lee Kuan Yew School of Public Policy at the National University of Singapore.

Members Events Team




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Will There Now Be Peace in the South China Sea?

14 July 2016

Bill Hayton

Associate Fellow, Asia-Pacific Programme
China’s sense of entitlement has collided with international law and, for the time being, lost. The way is open for a new regional understanding.

2016-07-14-Thitu.jpg

A member of the Philippines military stands on the beach at Thitu island, one of the disputed Spratly Islands. Photo by Getty Images.

The ruling by an arbitral tribunal of five members based in The Hague was simple and devastating. It declares that ‘China’s claims to historic rights… with respect to the maritime areas of the South China Sea encompassed by the relevant part of the “nine-dash line” are contrary to the [The UN] Convention [on the Law of the Sea, UNCLOS]’. This is a result that Southeast Asia’s maritime countries have long sought. The way is now clear to resolve all the disputes in the region, if the participants choose to do so.

For decades, countries around the South China Sea lived under the shadow of a quasi-territorial claim that no one really understood. What did the U-shaped, nine-dashed line marked on Chinese maps actually mean? In 2009, the Chinese government attached a copy of the map to an official submission to the UN Commission on the Limits of the Continental Shelf and the region became alarmed. For the first time, it seemed that China was serious about asserting a claim to all the land and water inside the line.

On Tuesday that claim was dismissed as entirely incompatible with international law. Moreover, the Arbitral Tribunal ruled that not one of the Spratly Islands qualifies as an ‘island’. This ruling is at least as significant: it means none of the features in the archipelago are entitled to an exclusive economic zone. Theoretically it should now be simple to resolve all the maritime disputes in the southern part of the South China Sea. The Philippines, Malaysia, Brunei, Indonesia and the Philippines can, in principle, draw lines up to 200 nautical miles out from their coasts and agree compromises where they overlap. China is now irrelevant to this process because its nearest coastline is simply too far away.

All the 50 or so features in the Spratly Islands that are naturally above water at high tide would be granted a 12-nautical-mile territorial sea. The resulting settlement would resemble a Swiss cheese: large areas of exclusive economic zone measured from national coastlines punctuated by a few dozen ‘bubbles’ of disputed territory. This would not resolve the disputes about which country is the rightful owner of those ‘bubbles’ but it would settle the maritime disputes in the sea around them.

Of course, there are still wrinkles. Not least is the Philippines claim to the Malaysian province of Sabah in northern Borneo. This means that, for the time being, those two countries can’t settle the maritime boundary between them. They could, nonetheless, agree how far it projects offshore.

The bigger problem will be China’s attitude. Its response to the tribunal’s ruling has been angry but curiously misdirected. State media have focused their ire on questions of territorial sovereignty – even though the tribunal was barred from even considering this subject. China’s territorial claims to the rocks of the Spratly Islands are entirely unaffected by Tuesday’s ruling. There must be separate processes to resolve those questions.

China has many interests in the South China Sea – including defence, trade routes, fisheries and hydrocarbons – so it’s not surprising that it pursues whatever approach it thinks practical in order to protect them. However, the whole purpose of the UN Convention on the Law of the Sea was to create an international order that defended the rights of countries to exploit the resources off their own coasts without threat from other states further away. China was a full participant in the negotiations between 1973 and 1982 that created UNCLOS and, at that time, was a strong defender of the rights of coastal countries.

While it may feel that it has lost out from this week’s ruling, China has much to gain from a strong community of regional order in the South China Sea. Most Southeast Asian countries remain alarmed by China’s intentions − which is why, in the past few years, they have been strengthening their ties with the United States and increasing military spending. China’s wider interests would benefit from a de-escalation of this tension. Reassuring its neighbours would give them less reason to rely on the US.

Putting a new maritime order in place, based upon UNCLOS and commitments between China and the Association of Southeast Asian Nations, would be a major step towards this. It would also bring many associated benefits – not least cooperation to protect the region’s fish stocks, which are facing disastrous collapse. The first step is accepting the implications of Tuesday’s ruling.

To comment on this article, please contact Chatham House Feedback




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Vortex Advertising CPA-network | Exclusive offers | Personal support




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ecommerce with specific functionality or requirements




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A former editor at the Observer says Kushner's claim of coronavirus 'success' stems from his inability to empathize with other people's grief

Elizabeth Spiers wrote about an incident where Jared Kushner used the memorial of an employee to congratulate himself for success.





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Meet the Ohio health expert who has a fan club — and Republicans trying to stop her

Some Buckeyes are not comfortable being told by a "woman in power" to quarantine, one expert said.





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As many as 75,000 could die from "deaths of despair" as a result of the coronavirus pandemic. One expert says economic turmoil has always led to an increase in suicides.

"I think it's always important to think about suicide as individual vulnerabilities and context," Eric Caine said.





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A photographer spent two weeks flying around in helicopters to capture the parked planes at US airports during the pandemic — see his eerie and beautiful work

Travel blogger and photographer Andy Luten drove 4,200 miles across six states to see the grounded jets, detailing the shocking state of aviation.





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Structures of the MHC-I molecule BF2*1501 disclose the preferred presentation of an H5N1 virus-derived epitope [Protein Structure and Folding]

Lethal infections by strains of the highly-pathogenic avian influenza virus (HPAIV) H5N1 pose serious threats to both the poultry industry and public health worldwide. A lack of confirmed HPAIV epitopes recognized by cytotoxic T lymphocytes (CTLs) has hindered the utilization of CD8+ T-cell–mediated immunity and has precluded the development of effectively diversified epitope-based vaccination approaches. In particular, an HPAIV H5N1 CTL-recognized epitope based on the peptide MHC-I–β2m (pMHC-I) complex has not yet been designed. Here, screening a collection of selected peptides of several HPAIV strains against a specific pathogen-free pMHC-I (pBF2*1501), we identified a highly-conserved HPAIV H5N1 CTL epitope, named HPAIV–PA123–130. We determined the structure of the BF2*1501–PA123–130 complex at 2.1 Å resolution to elucidate the molecular mechanisms of a preferential presentation of the highly-conserved PA123–130 epitope in the chicken B15 lineage. Conformational characteristics of the PA123–130 epitope with a protruding Tyr-7 residue indicated that this epitope has great potential to be recognized by specific TCRs. Moreover, significantly increased numbers of CD8+ T cells specific for the HPAIV–PA123–130 epitope in peptide-immunized chickens indicated that a repertoire of CD8+ T cells can specifically respond to this epitope. We anticipate that the identification and structural characterization of the PA123–130 epitope reported here could enable further studies of CTL immunity against HPAIV H5N1. Such studies may aid in the development of vaccine development strategies using well-conserved internal viral antigens in chickens.




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Structural insight into the recognition of pathogen-derived phosphoglycolipids by C-type lectin receptor DCAR [Protein Structure and Folding]

The C-type lectin receptors (CLRs) form a family of pattern recognition receptors that recognize numerous pathogens, such as bacteria and fungi, and trigger innate immune responses. The extracellular carbohydrate-recognition domain (CRD) of CLRs forms a globular structure that can coordinate a Ca2+ ion, allowing receptor interactions with sugar-containing ligands. Although well-conserved, the CRD fold can also display differences that directly affect the specificity of the receptors for their ligands. Here, we report crystal structures at 1.8–2.3 Å resolutions of the CRD of murine dendritic cell-immunoactivating receptor (DCAR, or Clec4b1), the CLR that binds phosphoglycolipids such as acylated phosphatidyl-myo-inositol mannosides (AcPIMs) of mycobacteria. Using mutagenesis analysis, we identified critical residues, Ala136 and Gln198, on the surface surrounding the ligand-binding site of DCAR, as well as an atypical Ca2+-binding motif (Glu-Pro-Ser/EPS168–170). By chemically synthesizing a water-soluble ligand analog, inositol-monophosphate dimannose (IPM2), we confirmed the direct interaction of DCAR with the polar moiety of AcPIMs by biolayer interferometry and co-crystallization approaches. We also observed a hydrophobic groove extending from the ligand-binding site that is in a suitable position to interact with the lipid portion of whole AcPIMs. These results suggest that the hydroxyl group-binding ability and hydrophobic groove of DCAR mediate its specific binding to pathogen-derived phosphoglycolipids such as mycobacterial AcPIMs.




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Kruppel-like factor 3 (KLF3) suppresses NF-{kappa}B-driven inflammation in mice [Immunology]

Bacterial products such as lipopolysaccharides (or endotoxin) cause systemic inflammation, resulting in a substantial global health burden. The onset, progression, and resolution of the inflammatory response to endotoxin are usually tightly controlled to avoid chronic inflammation. Members of the NF-κB family of transcription factors are key drivers of inflammation that activate sets of genes in response to inflammatory signals. Such responses are typically short-lived and can be suppressed by proteins that act post-translationally, such as the SOCS (suppressor of cytokine signaling) family. Less is known about direct transcriptional regulation of these responses, however. Here, using a combination of in vitro approaches and in vivo animal models, we show that endotoxin treatment induced expression of the well-characterized transcriptional repressor Krüppel-like factor 3 (KLF3), which, in turn, directly repressed the expression of the NF-κB family member RELA/p65. We also observed that KLF3-deficient mice were hypersensitive to endotoxin and exhibited elevated levels of circulating Ly6C+ monocytes and macrophage-derived inflammatory cytokines. These findings reveal that KLF3 is a fundamental suppressor that operates as a feedback inhibitor of RELA/p65 and may be important in facilitating the resolution of inflammation.




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Affinity maturation, humanization, and co-crystallization of a rabbit anti-human ROR2 monoclonal antibody for therapeutic applications [Immunology]

Antibodies are widely used as cancer therapeutics, but their current use is limited by the low number of antigens restricted to cancer cells. A receptor tyrosine kinase, receptor tyrosine kinase-like orphan receptor 2 (ROR2), is normally expressed only during embryogenesis and is tightly down-regulated in postnatal healthy tissues. However, it is up-regulated in a diverse set of hematologic and solid malignancies, thus ROR2 represents a candidate antigen for antibody-based cancer therapy. Here we describe the affinity maturation and humanization of a rabbit mAb that binds human and mouse ROR2 but not human ROR1 or other human cell-surface antigens. Co-crystallization of the parental rabbit mAb in complex with the human ROR2 kringle domain (hROR2-Kr) guided affinity maturation by heavy-chain complementarity-determining region 3 (HCDR3)-focused mutagenesis and selection. The affinity-matured rabbit mAb was then humanized by complementarity-determining region (CDR) grafting and framework fine tuning and again co-crystallized with hROR2-Kr. We show that the affinity-matured and humanized mAb retains strong affinity and specificity to ROR2 and, following conversion to a T cell–engaging bispecific antibody, has potent cytotoxicity toward ROR2-expressing cells. We anticipate that this humanized affinity-matured mAb will find application for antibody-based cancer therapy of ROR2-expressing neoplasms.




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Cell-specific expression of the transcriptional regulator RHAMM provides a timing mechanism that controls appropriate wound re-epithelialization [Glycobiology and Extracellular Matrices]

Prevention of aberrant cutaneous wound repair and appropriate regeneration of an intact and functional integument require the coordinated timing of fibroblast and keratinocyte migration. Here, we identified a mechanism whereby opposing cell-specific motogenic functions of a multifunctional intracellular and extracellular protein, the receptor for hyaluronan-mediated motility (RHAMM), coordinates fibroblast and keratinocyte migration speed and ensures appropriate timing of excisional wound closure. We found that, unlike in WT mice, in Rhamm-null mice, keratinocyte migration initiates prematurely in the excisional wounds, resulting in wounds that have re-surfaced before the formation of normal granulation tissue, leading to a defective epidermal architecture. We also noted aberrant keratinocyte and fibroblast migration in the Rhamm-null mice, indicating that RHAMM suppresses keratinocyte motility but increases fibroblast motility. This cell context–dependent effect resulted from cell-specific regulation of extracellular signal-regulated kinase 1/2 (ERK1/2) activation and expression of a RHAMM target gene encoding matrix metalloprotease 9 (MMP-9). In fibroblasts, RHAMM promoted ERK1/2 activation and MMP-9 expression, whereas in keratinocytes, RHAMM suppressed these activities. In keratinocytes, loss of RHAMM function or expression promoted epidermal growth factor receptor–regulated MMP-9 expression via ERK1/2, which resulted in cleavage of the ectodomain of the RHAMM partner protein CD44 and thereby increased keratinocyte motility. These results identify RHAMM as a key factor that integrates the timing of wound repair by controlling cell migration.




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Development of a novel {beta}-1,6-glucan-specific detection system using functionally-modified recombinant endo-{beta}-1,6-glucanase [Methods and Resources]

β-1,3-d-Glucan is a ubiquitous glucose polymer produced by plants, bacteria, and most fungi. It has been used as a diagnostic tool in patients with invasive mycoses via a highly-sensitive reagent consisting of the blood coagulation system of horseshoe crab. However, no method is currently available for measuring β-1,6-glucan, another primary β-glucan structure of fungal polysaccharides. Herein, we describe the development of an economical and highly-sensitive and specific assay for β-1,6-glucan using a modified recombinant endo-β-1,6-glucanase having diminished glucan hydrolase activity. The purified β-1,6-glucanase derivative bound to the β-1,6-glucan pustulan with a KD of 16.4 nm. We validated the specificity of this β-1,6-glucan probe by demonstrating its ability to detect cell wall β-1,6-glucan from both yeast and hyphal forms of the opportunistic fungal pathogen Candida albicans, without any detectable binding to glucan lacking the long β-1,6-glucan branch. We developed a sandwich ELISA-like assay with a low limit of quantification for pustulan (1.5 pg/ml), and we successfully employed this assay in the quantification of extracellular β-1,6-glucan released by >250 patient-derived strains of different Candida species (including Candida auris) in culture supernatant in vitro. We also used this assay to measure β-1,6-glucan in vivo in the serum and in several organs in a mouse model of systemic candidiasis. Our work describes a reliable method for β-1,6-glucan detection, which may prove useful for the diagnosis of invasive fungal infections.




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An enzyme-based protocol for cell-free synthesis of nature-identical capsular oligosaccharides from Actinobacillus pleuropneumoniae serotype 1 [Enzymology]

Actinobacillus pleuropneumoniae (App) is the etiological agent of acute porcine pneumonia and responsible for severe economic losses worldwide. The capsule polymer of App serotype 1 (App1) consists of [4)-GlcNAc-β(1,6)-Gal-α-1-(PO4-] repeating units that are O-acetylated at O-6 of the GlcNAc. It is a major virulence factor and was used in previous studies in the successful generation of an experimental glycoconjugate vaccine. However, the application of glycoconjugate vaccines in the animal health sector is limited, presumably because of the high costs associated with harvesting the polymer from pathogen culture. Consequently, here we exploited the capsule polymerase Cps1B of App1 as an in vitro synthesis tool and an alternative for capsule polymer provision. Cps1B consists of two catalytic domains, as well as a domain rich in tetratricopeptide repeats (TPRs). We compared the elongation mechanism of Cps1B with that of a ΔTPR truncation (Cps1B-ΔTPR). Interestingly, the product profiles displayed by Cps1B suggested processive elongation of the nascent polymer, whereas Cps1B-ΔTPR appeared to work in a more distributive manner. The dispersity of the synthesized products could be reduced by generating single-action transferases and immobilizing them on individual columns, separating the two catalytic activities. Furthermore, we identified the O-acetyltransferase Cps1D of App1 and used it to modify the polymers produced by Cps1B. Two-dimensional NMR analyses of the products revealed O-acetylation levels identical to those of polymer harvested from App1 culture supernatants. In conclusion, we have established a protocol for the pathogen-free in vitro synthesis of tailored, nature-identical App1 capsule polymers.




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Glycation-mediated inter-protein cross-linking is promoted by chaperone-client complexes of {alpha}-crystallin: Implications for lens aging and presbyopia [Glycobiology and Extracellular Matrices]

Lens proteins become increasingly cross-linked through nondisulfide linkages during aging and cataract formation. One mechanism that has been implicated in this cross-linking is glycation through formation of advanced glycation end products (AGEs). Here, we found an age-associated increase in stiffness in human lenses that was directly correlated with levels of protein–cross-linking AGEs. α-Crystallin in the lens binds to other proteins and prevents their denaturation and aggregation through its chaperone-like activity. Using a FRET-based assay, we examined the stability of the αA-crystallin–γD-crystallin complex for up to 12 days and observed that this complex is stable in PBS and upon incubation with human lens–epithelial cell lysate or lens homogenate. Addition of 2 mm ATP to the lysate or homogenate did not decrease the stability of the complex. We also generated complexes of human αA-crystallin or αB-crystallin with alcohol dehydrogenase or citrate synthase by applying thermal stress. Upon glycation under physiological conditions, the chaperone–client complexes underwent greater extents of cross-linking than did uncomplexed protein mixtures. LC-MS/MS analyses revealed that the levels of cross-linking AGEs were significantly higher in the glycated chaperone–client complexes than in glycated but uncomplexed protein mixtures. Mouse lenses subjected to thermal stress followed by glycation lost resilience more extensively than lenses subjected to thermal stress or glycation alone, and this loss was accompanied by higher protein cross-linking and higher cross-linking AGE levels. These results uncover a protein cross-linking mechanism in the lens and suggest that AGE-mediated cross-linking of α-crystallin–client complexes could contribute to lens aging and presbyopia.




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The Escherichia coli cellulose synthase subunit G (BcsG) is a Zn2+-dependent phosphoethanolamine transferase [Glycobiology and Extracellular Matrices]

Bacterial biofilms are cellular communities that produce an adherent matrix. Exopolysaccharides are key structural components of this matrix and are required for the assembly and architecture of biofilms produced by a wide variety of microorganisms. The human bacterial pathogens Escherichia coli and Salmonella enterica produce a biofilm matrix composed primarily of the exopolysaccharide phosphoethanolamine (pEtN) cellulose. Once thought to be composed of only underivatized cellulose, the pEtN modification present in these matrices has been implicated in the overall architecture and integrity of the biofilm. However, an understanding of the mechanism underlying pEtN derivatization of the cellulose exopolysaccharide remains elusive. The bacterial cellulose synthase subunit G (BcsG) is a predicted inner membrane–localized metalloenzyme that has been proposed to catalyze the transfer of the pEtN group from membrane phospholipids to cellulose. Here we present evidence that the C-terminal domain of BcsG from E. coli (EcBcsGΔN) functions as a phosphoethanolamine transferase in vitro with substrate preference for cellulosic materials. Structural characterization of EcBcsGΔN revealed that it belongs to the alkaline phosphatase superfamily, contains a Zn2+ ion at its active center, and is structurally similar to characterized enzymes that confer colistin resistance in Gram-negative bacteria. Informed by our structural studies, we present a functional complementation experiment in E. coli AR3110, indicating that the activity of the BcsG C-terminal domain is essential for integrity of the pellicular biofilm. Furthermore, our results established a similar but distinct active-site architecture and catalytic mechanism shared between BcsG and the colistin resistance enzymes.




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Endorepellin evokes an angiostatic stress signaling cascade in endothelial cells [Glycobiology and Extracellular Matrices]

Endorepellin, the C-terminal fragment of the heparan sulfate proteoglycan perlecan, influences various signaling pathways in endothelial cells by binding to VEGFR2. In this study, we discovered that soluble endorepellin activates the canonical stress signaling pathway consisting of PERK, eIF2α, ATF4, and GADD45α. Specifically, endorepellin evoked transient activation of VEGFR2, which, in turn, phosphorylated PERK at Thr980. Subsequently, PERK phosphorylated eIF2α at Ser51, upregulating its downstream effector proteins ATF4 and GADD45α. RNAi-mediated knockdown of PERK or eIF2α abrogated the endorepellin-mediated up-regulation of GADD45α, the ultimate effector protein of this stress signaling cascade. To functionally validate these findings, we utilized an ex vivo model of angiogenesis. Exposure of the aortic rings embedded in 3D fibrillar collagen to recombinant endorepellin for 2–4 h activated PERK and induced GADD45α vis à vis vehicle-treated counterparts. Similar effects were obtained with the established cellular stress inducer tunicamycin. Notably, chronic exposure of aortic rings to endorepellin for 7–9 days markedly suppressed vessel sprouting, an angiostatic effect that was rescued by blocking PERK kinase activity. Our findings unravel a mechanism by which an extracellular matrix protein evokes stress signaling in endothelial cells, which leads to angiostasis.




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Re: Covid-19: how to use your time when clinical placements are postponed - Wellbeing perspective




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Call for a review of services for people with neurological disorders




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US drug costs are rising faster than overall health spending, officials report




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Australian neuroscientist given two year suspended sentence for falsifying Parkinson's research