Thursday, October 21, 2021

Lab-grown ‘mini brains’ hint at treatments for neurodegenerative diseases

Mini brain organoids showing cortical-like structures 
Credit: Andras Lakatos
A common form of motor neuron disease, amyotrophic lateral sclerosis, often overlaps with frontotemporal dementia (ALS/FTD) and can affect younger people, occurring mostly after the age of 40-45. These conditions cause devastating symptoms of muscle weakness with changes in memory, behavior and personality. Being able to grow small organ-like models (organoids) of the brain allows the researchers to understand what happens at the earliest stages of ALS/FTD, long before symptoms begin to emerge, and to screen for potential drugs.

In general, organoids, often referred to as ‘mini organs’, are being used increasingly to model human biology and disease. At the University of Cambridge alone, researchers use them to repair damaged livers, SARS-CoV-2 infection of the lungs and model the early stages of pregnancy, among many other areas of research.

Typically, researchers take cells from a patient’s skin and reprogram the cells back to their stem cell stage – a very early stage of development at which they have the potential to develop into most types of cell. These can then be grown in culture as 3D clusters that mimic particular elements of an organ. As many diseases are caused in part by defects in our DNA, this technique allows researchers to see how cellular changes – often associated with these genetic mutations – lead to disease.

'Raptor-like’ dinosaur revealed to be a timid vegetarian

A life-reconstruction of herbivorous dinosaurs based on 220-million-year-old fossil footprints from Ipswich, Queensland, Australia.Image credit: Anthony Romilio.

The dinosaur footprint is on display at the
Queensland Museum, Brisbane.
Fossil footprints found in an Ipswich coal mine have long been thought to be that of a large ‘raptor-like’ predatory dinosaur, but scientists have found they were instead left by a timid long-necked herbivore.

University of Queensland paleontologist Dr Anthony Romilio recently led an international team to re-analyze the footprints, dated to the latter part of the Triassic Period, around 220 million-year-ago.

“For years it’s been believed that these tracks were made by a massive predator that was part of the dinosaur family Eubrontes, with legs over two meters tall,” Dr Romilio said.

“This idea caused a sensation decades ago because no other meat-eating dinosaur in the world approached that size during the Triassic period.

“But our research shows the tracks were instead made by a dinosaur from the Evazoum family – vegetarian dinosaurs that were smaller, with legs about 1.4 meters tall and a body length of six meters.”

The research team suspected there was something not-quite-right with the original size estimates and there was a good reason for their doubts.

A crab’s inland odyssey

Researchers have discovered the oldest known modern crab — trapped in amber since the time of the dinosaurs.

The 100-million-year-old fossil of the crab, Cretapsara athanata, comes from Myanmar, in Southeast Asia. It fills a major gap in the fossil record for crabs and resets the timetable for when marine crabs made their way inland.

Yale and Harvard paleontologists led the research, which appears in the journal Science Advances.

“This discovery, in a pristine and spectacular 3D preservation — including fine details of the eyes, antennae, mouthparts, and even the gills — represents the oldest evidence of incursions into land and freshwater by crabs,” said co-lead author Javier Luque, a former Yale researcher who is now a research associate at Harvard. “Crabs are primarily a marine group that only conquered land and freshwater much later, about 75 to 50 million years ago. They are largely known by bits and pieces of their claws — never in the stunning detail of our new discovery.”

The researchers said the new species, Cretapsara, was most likely neither a marine crab nor a fully terrestrial creature. Rather, Cretapsara was a freshwater-to-amphibious crab that lived either on the forest floor or in shallow bodies of water near the forest floor.

To selectively kill cancer cells, target a protein channel in the cell's lysosome

Cancer treatments necessarily target unchecked cell growth, and selectively kill cancer cells while sparing normal cells and avoiding general toxicity in the human body.

To develop new treatments for cancer, scientists are focused on finding the malfunctioning machinery within cancer cells that can be targeted using small molecule pharmaceuticals. Now, University of Michigan researchers have identified one of these targets: a zinc and calcium ion permeable channel within a cell’s lysosome, the organelle responsible for recycling cellular waste, nutrient sensing and cell metabolism.

The researchers discovered that this channel is upregulated—meaning both its protein expression and channel activity were substantially increased—in metastatic melanoma cells compared with healthy melanocytes. They found that targeting this channel protein with small pharmaceutical compounds triggers the rapid and selective death of cancer cells while completely sparing normal cells. Their research is published in the journal Cell Reports.

“Many traditional cancer therapies target a well-known cell death pathway called apoptosis to trigger cancer cell death. However, many aggressive cancer cells harbor numerous mutations of genes that help them escape these treatments. We saw an urgent need to develop new therapeutic strategies that target nonapoptotic cell death pathways to eradicate cancer cells,” said Wanlu Du, an assistant research scientist in the U-M Department of Molecular, Cellular, and Developmental Biology.

In metastatic cancers, lysosomes turn hypertrophic, which means they actively contribute to tumor progression by increasing their ability to provide nutrients to the rapidly dividing cells and secreting enzymes to digest extracellular matrix—the material that provides the physical scaffolding for cells to help cancer cell invasion. But designing cancer therapies that target lysosomes may also harm normal cells and tissues by compromising lysosomes’ ability to provide nutrients for healthy cells.

Changing Ocean Currents Are Driving Extreme Winter Weather

Transmission towers and lines were covered in snow in East Texas. The state experienced a power crisis during severe winter storms in February, resulting in about $20 billion in socioeconomic damages, according to NOAA. Credit: Matthew Rader

Throughout Earth's oceans runs a conveyor belt of water. Its churning is powered by differences in the water's temperature and saltiness, and weather patterns around the world are regulated by its activity.

A pair of researchers studied the Atlantic portion of this worldwide conveyor belt called the Atlantic Meridional Overturning Circulation, or AMOC, and found that winter weather in the United States critically depends on this conveyor belt-like system. As the AMOC slows because of climate change, the U.S. will experience more extreme cold winter weather.

The study, published in the journal Communications Earth & Environment was led by Jianjun Yin, an associate professor in the University of Arizona Department of Geosciences and co-authored by Ming Zhao, a physical scientist at the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory.

AMOC works like this: Warm water travels north in the upper Atlantic Ocean and releases heat into the atmosphere at high latitudes. As the water cools, it becomes denser, which causes it to sink into the deep ocean where it flows back south.

Researchers identify new pathways to target breast cancer

A pathway helping the breast cancer protein BRCA1 repair damaged DNA has been identified by University of Queensland researchers in a study that will inform future targeted therapies.

Professor Robert Parton, Professor Alpha Yap and Dr Kerrie-Ann McMahon from UQ’s Institute for Molecular Bioscience (IMB) identified an association between two proteins that are lost in cancer cells – the well-known BReast CAncer gene 1 (BRCA1) and a new player - cavin3.

“In healthy cells, BRCA1 repairs DNA damage and suppresses tumor formation, but cells with mutations in their BRCA1 genes struggle to keep up with DNA repairs, which is when cancer can take over,” Dr McMahon said.

“We discovered that cavin3 helps BRCA1 function when cells are stressed and that when it’s absent, levels of BRCA1 decrease.

Putting the fire lookout in orbit

Image: / Alexpunker

OroraTech, a startup formed at the Technical University of Munich (TUM), is preparing to launch a fleet of small satellites. They will use infrared cameras to detect temperature anomalies at high temporal and spatial resolutions. With the data, the young entrepreneurs want to localize forest fires quickly and track their spread in real time.

Extreme weather events are becoming more frequent everywhere in the world: Even at higher latitudes where heat waves and droughts were rare in the past, the risk of forest fires is on the increase. Dry conditions and winds cause the fires to spread and go out of control faster. Forest and bush fires not only destroy vegetation − they also fuel climate change.

“If we want to fight forest and bush fires, stop illegal slash-and-burn activity and thus reduce CO2 emissions, we need a global early warning system,” says Thomas Grübler, one of the founders of the OroraTech startup. At present it can take several hours or even days before a fire source is identified and reported by ground-based fire watch crews, aircraft or drones, he explains. That may be long enough for a fire to spread over a considerable area. "Satellites facilitate quicker and more targeted tracking of forest fires. With this information, fire crews on the ground can fight fires faster and more precisely,” adds Grübler.

Wednesday, October 20, 2021

Researchers Join Fight to Save the Coral

An underwater view of one of the ark structures
being used by SDSU researchers to protect coral reefs.
(Photo: Jason Baer)
Ph.D. candidate Jason Baer and the Rohwer Lab team are deploying first-of-their-kind floating structures in an attempt to rebuild damaged reefs.

San Diego State University Ph.D. candidate Jason Baer is on a mission to restore coral reefs that have been damaged by climate change, overfishing or tourism by using ark structures, the first of their kind.

Baer and his fellow lab members, led by SDSU microbial ecologist and virologist Forest Rohwer, deploy the large, geodesic structures in the midwater above the ocean floor and seed them with corals and organisms that support their health. The arks, similar to the Noah’s Ark concept, give the threatened communities of coral a second chance to thrive.

Their positioning in midwater, where there’s higher light and flow, offers an improved environment for corals and their allies and distances them from some of the stressors they face on the seafloor, such as sedimentation and suffocation.

Baer, along with Rohwer lab members Anneke van der Geer, Andres Sanchez-Quinto, and Mark Little, spent six weeks in Curaçao, a Caribbean island, working with the CARMABI marine station this past summer. Together they deployed the first arks on coral reefs and began studying the communities that recruited them, with the goal of watching a reef community “build” itself.

Radioactive metals could eventually be used in next-generation cancer therapies

Actinium is a radioactive element that could revolutionize cancer medicine but its chemistry has thus far remained elusive. LLNL and Penn State researchers developed a new approach to study, capture, and purify medical isotopes, including actinium, which leverages a natural protein.
Image Credit: Thomas Reason/LLNL

A protein can be used to recover and purify radioactive metals such as actinium that could be beneficial for next-generation drugs used in cancer therapies and medical imaging, according to new research from Penn State and Lawrence Livermore National Laboratory (LLNL).

Radioactive metals are used in a variety of medical imaging and therapeutic applications. Actinium is a promising candidate for next-generation cancer therapies, and actinium-based therapies have treatment efficacy hundreds of times higher than current drugs. However, the chemistry of this metal is not well understood, and there are several limitations in the supply chain that have kept actinium-based drugs from reaching the market.

“In this study, our team took advantage of a protein my lab previously discovered called lanmodulin and showed that it can be used to improve and simplify the recovery and purification of actinium,” said Joseph Cotruvo Jr., assistant professor of chemistry at Penn State and an author of the paper. The research team presents their results in a paper appearing Oct. 20 in the journal Science Advances.

Electron quadruplets

Electron quadruplets were observed in this iron-based superconductor material, Ba1−xKxFe2As2, seen mounted for experimental measurements in Professor Babaev's research.
(Photo: Vadim Grinenko, Federico Caglieris)

For nearly 20 years, Egor Babaev has sought to show a new state of matter—electron quadruplets. Now he has found what he was looking for.

The central principle of superconductivity is that electrons form pairs. But can they also condense into foursomes? Recent findings have suggested they can, and a physicist at KTH published the first experimental evidence of this quadrupling effect and the mechanism by which this state of matter occurs.

KTH Professor Egor Babaev, together with international collaborators, presented evidence of fermion quadrupling in a series of experimental measurements on the iron-based material, Ba1−xKxFe2As2. Published in Nature Physics, the results follow nearly 20 years after Babaev first predicted this kind of phenomenon (Read Egor Babaev's 2004 paper), and eight years after he published a paper predicting that it could occur in the material.

The pairing of electrons enables the quantum state of superconductivity, a zero-resistance state of conductivity which is used in MRI scanners and quantum computing. It occurs within a material as a result of two electrons bonding rather than repelling each other, as they would in a vacuum. The phenomenon was first described in a theory by, Leon Cooper, John Bardeen and John Schrieffer, whose work was awarded the Nobel Prize in 1972.

Humans caused climate change

More than 99.9% of peer-reviewed scientific papers agree that climate change is mainly caused by humans, according to a new survey of 88,125 climate-related studies.

The research updates a similar 2013 paper revealing that 97% of studies published between 1991 and 2012 supported the idea that human activities are altering Earth’s climate. The current survey examines the literature published from 2012 to November 2020 to explore whether the consensus has changed.

“We are virtually certain that the consensus is well over 99% now and that it’s pretty much case closed for any meaningful public conversation about the reality of human-caused climate change,” said Mark Lynas, a visiting fellow at the Alliance for Science and the paper’s first author.

“It's critical to acknowledge the principal role of greenhouse gas emissions so that we can rapidly mobilize new solutions, since we are already witnessing in real time the devastating impacts of climate related disasters on businesses, people and the economy,” said Benjamin Houlton, the Ronald P. Lynch Dean of the College of Agriculture and Life Sciences and a co-author of the study, “Greater than 99% Consensus on Human Caused Climate Change in the Peer-Reviewed Scientific Literature,” which published Oct. 19 in the journal Environmental Research Letters.

Treating opioid use disorder in remote areas

The most sparsely populated regions of the American West often are unable to provide local treatment for opioid use disorder. Long driving distances can be a barrier for people who need treatment, so the issue has ramifications for the health and wellness of many residents across the most rural areas of the country.

A team of researchers from Penn State and JG Research and Evaluation recently examined the effectiveness of a successful model for rural treatment of opioid use disorder in Montana, one of the nation’s most sparsely populated states.

“When states develop treatment models for opioid use disorder, public health officials must account for local variations in culture, stigma, and access to resources."
Danielle Rhubart, assistant professor of biobehavioral health

Opioids are highly addictive, and opioid use disorder is difficult to treat. Fortunately, many people who experience opioid use disorder can reach recovery. Most treatment programs, however, are very intensive and require specialized care, highly regulated medication, and daily or weekly clinical visits. Because of this intensive specialization, people in rural areas who experience opioid use disorder often lack access to local treatment.

To address the lack of services for people with opioid use disorder in rural areas, researchers and clinicians in Vermont developed a model of care for opioid treatment. People with opioid use disorders from remote areas are stabilized at addiction care facilities in more populous areas and then receive ongoing care at rural primary care clinics that have established partnerships with these addiction care facilities. Based on this model’s success in Vermont, it has been deployed in many rural areas across the nation.

Get your kids ages 5-11 vaccinated once approved

Vaccination will help break the cycle of frequent PCR testing, quarantining, isolation

Parents are likely to learn around Halloween whether the U.S. Food and Drug Administration (FDA) has approved Pfizer’s COVID-19 vaccine for 5- to 11-year-old children. While some families are champing at the bit to schedule their kids’ first shot, polling suggests many remain hesitant.

But parents should feel confident getting their young children vaccinated as soon as the FDA gives the green light and it becomes available, said Northwestern University Feinberg School of Medicine pediatric experts Dr. Nina Alfieri and Dr. Jennifer Kusma, both of whom are advanced general pediatric and primary care physicians at the Ann & Robert H. Lurie Children’s Hospital of Chicago.

“Vaccinating this group of children is going to be helpful for them staying in school, getting back to their routines, protecting their grandparents and allowing their parents to keep working and doing their interests and daily activities,” Alfieri said. “Kids thrive on consistency. Protecting children with vaccination is an important step in helping break the cycle of kids needing frequent PCR testing and quarantining with each sick symptom they have. This could allow children to have a more consistent routine in addition to protecting their physical health.”

Extinct ground sloth was an omnivore

Julia Tejada sampling a specimen of the North American ground sloth.
(Copyright: Julia Tejada)
A study co-authored by University of Hawaiʻi at Mānoa scientists suggests that Mylodon—a ground sloth that lived in South America until about 10,000 to 12,000 years ago—was not a strict vegetarian like all of its living relatives. Based on a chemical analysis of amino acids preserved in sloth hair, the researchers uncovered evidence that this gigantic extinct sloth was an omnivore, at times eating meat or other animal protein in addition to plant matter.

Led by researchers at the American Museum of Natural History and published in Scientific Reports, the study contradicts previous assumptions about the animal and provides the first direct evidence of omnivory in an ancient sloth species.

Even though the six living sloth species all are relatively small plant-eating tree dwellers restricted to tropical forests of Central and South America, hundreds of fossil sloth species, some as large as an elephant, roamed ancient landscapes from Alaska to the southern tip of South America. Mylodon darwinii, also known as “Darwin’s ground sloth,” is thought to have weighed between 2,200 and 4,400 pounds and was nearly 10 feet long.

Based on dental characteristics, jaw biomechanics, preserved excrement from some very recent fossil species, and the fact that all living sloths exclusively eat plants, Mylodon and its extinct relatives have long been presumed to be herbivores as well. But these factors could not directly reveal whether an animal might have ingested food that requires little or no preparation and is completely digested, as happens in carcass scavenging or some other kinds of meat eating.

New tool can identify harmful blue-green algae

A new way to detect early signs of harmful blue-green algae, which bloom in lakes, rivers and reservoirs around the world, has been developed by researchers at the University of Birmingham together with researchers at the Culture Collection of Algae & Protozoa (CCAP), based at the Scottish Association of Marine Science.

Blue-green algae, or cyanobacteria, present huge environmental problems. Large scale break-outs, or blooms, spread across bodies of water, depleting the oxygen supply and reducing light, killing fish and other aquatic animals. In addition, some algae can produce toxins that are harmful to animals and humans.

Detecting these blooms – at a sufficiently early stage to prevent them reaching dangerous levels – is not straightforward because of the thousands of different species of algae that could be present. As algae are a vital part of many water systems, it is only those species which become harmful that may need these preventative measures.

Researchers in the University of Birmingham’s School of Biosciences have designed a new approach which uses mass spectrometry – a way of identifying specific molecules by their mass – to identify key protein features within the algae that are unique to each species, enabling them to be rapidly identified. Using recently developed, high resolution techniques, the team found they were able to produce highly specific ‘fingerprints’ that each correspond to specific cyanobacterial species. The work is published in Analytical Chemistry.

Tuesday, October 19, 2021

Physicists announce results that boost evidence for new fundamental physics

View of the LHCb detector 
Credit: CERN
In March 2020, the same experiment released evidence of particles breaking one of the core principles of the Standard Model – our best theory of particles and forces – suggesting the possible existence of new fundamental particles and forces.

Now, further measurements by physicists at Cambridge’s Cavendish Laboratory have found similar effects, boosting the case for new physics.

The Standard Model describes all the known particles that make up the universe and the forces that they interact through. It has passed every experimental test to date, and yet physicists know it must be incomplete. It does not include the force of gravity, nor can it account for how matter was produced during the Big Bang, and contains no particle that could explain the mysterious dark matter that astronomy tells us is five times more abundant than the stuff that makes up the visible world around us.

As a result, physicists have long been hunting for signs of physics beyond the Standard Model that might help us to address some of these mysteries.

One of the best ways to search for new particles and forces is to study particles known as beauty quarks. These are exotic cousins of the up and down quarks that make up the nucleus of every atom.

Electric trucks: ultra-fast charging in the megawatt range

Trucks with electric drives could soon be used in long-distance transport.
Image: / Chesky_W

It is an ambitious goal: By 2030 the German government aims to reduce carbon dioxide emissions by 65 percent compared to 1990. But how? With partners from industry and research institutes, scientists at the Technical University of Munich (TUM) are working on prototypes for an electric-powered truck and the charging station it will need.

“Freight transport on our roads is responsible for more than one third of our national greenhouse gas emissions,” says Sebastian Wolff of the TUM Chair of Automotive Technology. Consequently, new truck concepts will be needed if Germany wants to drastically cut its CO2 emissions by 2030.

In the NEFTON project, which is funded by the Federal Ministry of the Economy, engineers working in industry and research are developing a prototype for an electric truck and a charging station to power it.

The first battery-powered truck prototypes are currently being tested with customers serving short-haul routes. A long-haul truck needs to cover 500 kilometers or more in a day, however. That means that the battery would have to be charged at least on a daily basis. That would be a big adjustment for drivers, who currently visit a gas station perhaps once in five days.

Untangling the heart’s genome: now in 3D

Research led by Australian Regenerative Medicine Institute and Monash Biomedicine Discovery Institute (BDI) researchers at Monash University has combined cutting-edge genomics and 3D “gaming” modelling to understand how all genes are expressed in different parts of the heart, unveiling complex patterns and novel markers. To help visualize this new research, the team, led by Monash group leaders Associate Professor Mirana Ramialison and Professor Jose Polo in collaboration with Dr Fernando Rossello, has developed a powerful tool called 3D-cardiomics.

This work has been recently published in the Journal of Molecular and Cellular Cardiology.

“One of the outstanding challenges in genomics research is understanding the physical context,” noted Associate Professor Ramialison, who has recently moved her research group to the Murdoch Children Research Institute to continue her work in heart development and genomics. “We can detect when gene expression is up or down-regulated in any number of tissues on a global level, but what is more complicated is understanding the spatial relationships in three dimensions. This is key to uncovering developmental and physiological processes of the heart, during both homeostasis and disease.”

The research team micro dissected and sequenced transcriptome-wide 18 anatomical sections of the adult mouse heart with this aim in mind. The study results unveiled known and novel genes that display complex spatial expression across the heart sub-compartments.

Interferon does not improve outcomes for hospitalized adults with COVID-19

Colorized scanning electron micrograph of a human cell
heavily infected with SARS-CoV-2 virus particles (red). NIAID
 A clinical trial has found that treatment with the immunomodulator interferon beta-1a plus the antiviral remdesivir was not superior to treatment with remdesivir alone in hospitalized adults with COVID-19 pneumonia. In addition, in a subgroup of patients who required high-flow oxygen, investigators found that interferon beta-1a was associated with more adverse events and worse outcomes. These findings were published today in the journal The Lancet Respiratory Medicine.

The study, called the Adaptive COVID-19 Treatment Trial 3 (ACTT-3), took place from August 5, 2020 to December 21, 2020. It was sponsored and funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

Interferon beta-1a has the same amino acid sequence as a naturally occurring protein called interferon beta, which is in a class of proteins called type 1 interferons. Infected cells normally produce type 1 interferons to help the immune system fight pathogens, especially viruses. Interferon beta has both antiviral and anti-inflammatory properties.

Laboratory studies have shown that the normal type 1 interferon response is suppressed after infection with SARS-CoV-2, the virus that causes COVID-19. In addition, previous studies of hospitalized patients with COVID-19 demonstrated reduced production of interferon in response to SARS-CoV-2 infection in many patients, and this was associated with more severe disease. Other laboratory studies and clinical data supported the hypothesis that treatment with interferon beta-1a might improve health outcomes in people with COVID-19.

Monday, October 18, 2021

Fasting is required to see the full benefit of calorie restriction in mice

Over the last few decades, scientists have discovered that long-term calorie restriction provides a wealth of benefits in animals: lower weight, better blood sugar control, even longer lifespans.

Researchers have largely assumed that reduced food intake drove these benefits by reprogramming metabolism. But a new study from University of Wisconsin­–Madison researchers finds that reduced calorie intake alone is not enough; fasting is essential for mice to derive full benefit.

The new findings lend support to preliminary evidence that fasting can boost health in people, as trends like intermittent fasting continue to hold sway. These human and animal studies have added to the growing picture of how health is controlled by when and what we eat, not just how much.

The research further emphasizes the complexity of nutrition and metabolism and provides guidance to researchers trying to untangle the true causes of diet-induced health benefits in animals and humans.

The researchers discovered that, combined with eating less, fasting reduces frailty in old age and extends the lifespan of mice. And fasting alone can improve blood sugar and liver metabolism.

Surprisingly, mice that ate fewer calories but never fasted died younger than mice that ate as much as they wanted, suggesting that calorie restriction alone may be harmful.

Cell fitness used to determine outcomes in COVID patients

Cell fitness has been identified as a way of predicting health outcomes in COVID patients, according to a University of Queensland study.

The study investigated a cellular fitness marker, known as hfwe-Lose, to identify sub-optimal cells in patients who had been hospitalized or died from COVID at the start of the pandemic.

UQ Diamantina Institute’s Dr Arutha Kulasinghe said researchers conducted post-mortem analysis on COVID-infected lung tissues and found that the cell fitness marker influenced a person’s immune response to infection.

“We found that patients with acute lung injury had higher levels of the biomarker in their lower respiratory tract and areas of cell death,” Dr Kulasinghe said.

“More importantly, we also found that the cell fitness marker outperformed conventional methods, such as age, inflammation and co-existing diseases, in predicting health outcomes, such as hospitalization and death, in COVID patients.”

Assessing the level of risk in developing severe COVID infection is an important consideration in the management of the current pandemic.

Dr Kulasinghe said the study findings might be useful in the early triage of patients who test positive for COVID as the cell fitness marker could be identified via a simple nasal swab.

“The cell fitness marker would enable medical teams to identify patients more likely to develop severe symptoms, provide closer monitoring and earlier access to hospitalization and intensive care,” he said.

“We are now looking to validate our findings in larger patient populations to determine the robustness of the marker.

“The cell fitness marker is part of the body’s process for removing unwanted cells."

This study was conducted in partnership with the University of Copenhagen

Source/Credit: University of Queensland


J&J coronavirus vaccine produces low antibody response

Photo by Frank Merino from Pexels
In a head-to-head comparison of the three widely used coronavirus vaccines in the United States, the Johnson & Johnson vaccine yielded a strikingly lower antibody response in a Stanford School of Medicine-led study published in the Journal of the American Society of Nephrology.

The study, which analyzed early vaccine immune response in 2,099 dialysis patients, found that 33% of those vaccinated with Johnson & Johnson did not develop coronavirus antibodies, compared with 4% of those who received the Pfizer-BioNTech vaccine and 2% who received the Moderna vaccine. The study is one of the first to compare immune response associated with antibody levels using the same blood test for all three vaccines.

“We weren’t expecting this large a difference between vaccines,” said Shuchi Anand, MD, assistant professor of nephrology and a lead author of the study. “Since part of the rationale for boosters is waning antibody response, our study strongly argues for the need for booster shots for Johnson & Johnson, particularly in the immunocompromised population.”

Less protection

Pablo Garcia, MD, a postdoctoral scholar in nephrology and co-lead author of the study, agreed that people vaccinated with the J&J vaccine are probably less protected from the coronavirus and will “most likely need a booster shot.”

The researchers, who set out to analyze antibody response in the early post-vaccination period, collaborated with a nonprofit dialysis provider that treats kidney patients undergoing dialysis in California, Tennessee, Texas and New Jersey. The tests were conducted between 28 and 60 days after each patient had been fully vaccinated.

A new treatment for glaucoma?

Photo by Ksenia Chernaya from Pexels
A Northwestern Medicine study in mice has identified new treatment targets for glaucoma, including preventing a severe pediatric form of glaucoma, as well as uncovering a possible new class of therapy for the most common form of glaucoma in adults.

In people with high pressure glaucoma, fluid in the eye doesn’t properly drain and builds up pressure on the optic nerve, leading to vision loss. It affects 60 million people worldwide and is the most common cause of blindness in people over 60 years old.

While there are a few treatments available for open angle glaucoma, the most common form of glaucoma in adults (eye drops, oral medication, laser treatments), there are no cures, and a severe form of glaucoma in children between birth and three years old known as primary congenital glaucoma can only be treated with surgery.

“Although primary congenital glaucoma is much rarer than open angle glaucoma, it is devastating for children,” said corresponding author Dr. Susan Quaggin, chief of nephrology and hypertension in the Department of Medicine at Northwestern University Feinberg School of Medicine. “New treatments and new classes of treatments are urgently needed to slow vision loss in both forms.

Using gene editing, the scientists in the study developed new models of glaucoma in mice that resembled primary congenital glaucoma. By injecting a new, long-lasting and non-toxic protein treatment (Hepta-ANGPT1) into mice, the scientists were able to replace the function of genes that, when mutated, cause glaucoma. With this injectable treatment, the scientists also successfully prevented glaucoma from ever forming in one model. This same therapy, when injected into the eyes of healthy adult mice, reduced pressure in the eyes, supporting it as a possible new class of therapy for the most common cause of glaucoma in adults (high intraocular pressure open angle glaucoma).

The study, “Cellular crosstalk regulates the aqueous humor outflow pathway and provides new targets for glaucoma therapies," was published Oct. 18 in the journal Nature Communications. (PDF)

The next step is to develop the appropriate delivery system for the successful new protein treatment in patients and bring it to production, Quaggin said.

Uncovering the secrets of ultra-low frequency gravitational waves

An artist's impression of the colliding bubbles that can produce extremely low frequency gravitational waves during a cosmological phase transition in the early Universe.
Image credit: Riccardo Buscicchio.

New methods of detecting ultra-low frequency gravitational waves can be combined with other, less sensitive measurements to deliver fresh insights into the early development of our universe, according to researchers at the University of Birmingham.

Gravitational waves - ripples in the fabric of Einstein's spacetime - that cross the universe at the speed of light have all sorts of wavelengths, or frequencies. Scientists have not yet managed to detect gravitational waves at extremely low ‘nanohertz’ frequencies, but new approaches currently being explored are expected to confirm the first low frequency signals quite soon.

The main method uses radio telescopes to detect gravitational waves using pulsars – exotic, dead stars, that send out pulses of radio waves with extraordinary regularity. Researchers at the NANOGrav collaboration, for example, use pulsars to time to exquisite precision the rotation periods of a network, or array, of millisecond pulsars – astronomers’ best approximation of a network of perfect clocks - spread throughout our galaxy. These can be used to measure the fractional changes caused by gravitational waves as they spread through the universe.

How can we eat without cooking the planet?

Oxford experts in the run up to the COP26 climate conference, Professor Jebb points out that agriculture accounts for more CO2 emissions than transportation, and she says ‘It is the single biggest cause of harm to nature.’   We need governments to make some structural changes in the food system, says Professor Jebb, but, meanwhile, we can all make a start by doing three things:    Avoid eating too much  Cut down on waste  Reduce consumption of meat and dairy

She says, some people have given up meat altogether but, Professor Jebb maintains, 'Although animals produce emissions, they are an important part of our agriculture eco-systems and provide important nutrients.'   But we need to reduce the global demand for meat, so countries that currently eat a lot of meat need to cut down. That would be good for health and the environment.  ‘Eating less meat will be  a win for people and the planet,’ she says.

Source/Credit: University of Oxford


Genetic risk for clinical depression linked to physical symptoms

Dr Enda Byrne
People with higher genetic risk of clinical depression are more likely to have physical symptoms such as chronic pain, fatigue and migraine, University of Queensland researchers have found.

Dr. Enda Byrne from UQ’s Institute for Molecular Bioscience said depression was a serious disorder with lifetime risks of poor health.

“A large proportion of people with clinically-diagnosed depression present initially to doctors with physical symptoms that cause distress and can severely impact on people’s quality of life,” Dr. Byrne said.

Our research aimed to better understand the biological basis of depression and found that assessing a broad range of symptoms was important.

“Ultimately, our research aimed to better understand the genetic risks and generate more accurate risk scores for use in research and healthcare.”

Despite recent breakthroughs, Dr. Byrne said finding additional genetic risk factors was difficult because of the variety of patient ages, their symptoms, responses to treatment and additional mental and physical disorders.

Sunday, October 17, 2021

Invasive Species Increasingly Threaten Protected Areas Worldwide

China's famous Red Marshes, a protected area and vital shorebird
habitat that is increasingly being overrun by invasive grasses
that are smothering the red plants.
Photo credit: Hong'an Ding
The iconic “Red Beach” marshes of China’s Yellow Sea are a critical stopover for millions of shorebirds on their seasonal migrations along the East Asian-Australasian Flyway.

But in recent years, the vivid scarlet-hued native succulent plants that give the marshes their name are increasingly being overrun by non-native invasive grasses that are turning the marshes, which the Chinese government has set aside as a protected area, into a green desert avoided by shorebirds.

A new international study suggests similar scenarios may be playing out in many protected areas worldwide.

“Invasive species such as the cordgrass that is swamping native plants in the Red Marshes pose a much greater threat to protected areas, even well managed ones, than was previously recognized,” says Brian Silliman, Rachel Carson Distinguished Professor of Marine Conservation Biology at Duke University, who co-authored the study.

“Our findings suggest it may no longer be enough to defend these coastal areas of great ecological importance from disturbances by human activities,” says lead author Qiang He, a former postdoctoral researcher in Silliman’s lab who is now a professor of coastal ecology at Fudan University in China. “We also need to find better ways to protect them from biological invaders like cordgrass, which thrive in the open habitat of low-elevation mudflats that are a preferred habitat of shorebirds and common at many of these sites.”

Silliman, He and their colleagues published their peer-reviewed study Oct. 13 in the journal Science Advances. It was selected by the journal’s editors to be the issue’s cover article.

To conduct their study, the researchers used remote sensing to analyze 30 years of Google Earth Engine satellite images of wetlands inside and outside of seven of China’s largest protected coastal areas on the Yellow Sea, including several World Natural Heritage sites and Wetlands of International Importance sites.

By measuring and comparing the speed and extent of both wetland loss - typically caused by human disturbance – and cordgrass invasion at each site, they were able to construct a time-series dataset that shows native plants and habitats within the protected areas do receive protection, just not always enough.

“Although wetland loss due to human disturbance was significantly slower in all protected areas than in the unprotected control sites, plant invasions were much higher in four of the protected areas under invasion,” says He.

That finding confounds the prevailing theory that disturbance promotes species invasions, says Silliman.

“Compared to protected areas, unprotected sites often experience strong human disturbance, have more open habitats and are, thus, expected to be more vulnerable to invasions by exotic species,” he says. “We found it’s not that cut and dried.”

“Most importantly, our findings caution blind acceptance of the current conservation paradigm that protected areas will work well as long as human activities are managed effectively. This study shows that even if they are, invasive species can wreck that feel-good party,” he says. Silliman directs the Duke Restore initiative, which brings together researchers from science, engineering and policy to develop more effective tools and practices to combat habitat loss and enhance the resilience of natural and human systems in coastal areas. Qiang He is a visiting scholar in the program.

Their new study’s publication coincided with the 15th meeting of the Conference of the Parties (COP15) United Nations Convention on Biological Diversity in Kunming, China.

Leaders from more than 100 nations attended the meeting. They called for “urgent and integrated action” to increase the emphasis placed on biodiversity protection in all sectors of the global economy but stopped short of committing to specific targets to slow species loss, including a long-debated proposal to protect or conserve 30% of the land and ocean within their national territories by 2030.

Funding for the new study came from the National Natural Science Foundation of China and the National Key Research and Development Program of China.

Source/Credit: Duke University/Brian Silliman


Friday, October 15, 2021

Carbon from a cosmic source

Partners in space: massive stars often occur in close binary systems in which one star takes mass from its companion. New research has now shown that these systems produce about twice as much carbon as individual, massive stars. © ESO/M. Kornmesser / S.E. de Mink
Computer simulations show that binary stars produce a large amount of this vital element

Many things work better in pairs. The production of chemical elements is no exception. Many elements are formed inside stars during fusion processes. Carbon plays an important role in this because it is the basis of life and thus ultimately of human beings. But how effective is the cosmic source of this important building block? A study led by the Max Planck Institute for Astrophysics shows that massive stars produce twice as much carbon when they have a companion star.

The researchers know that massive stars are essential in the synthesis of all heavy elements – from carbon and oxygen to iron. Although most of these stellar heavyweights are born in multiple star systems, previous models have looked almost exclusively at single stars. An international team led by Robert Farmer from the Max Planck Institute for Astrophysics in Garching has now calculated the carbon footprint of massive stars that are partners in a binary system.

The Butterfly Effect

Collected butterfly specimens from Torres Strait.
Image; Dr Trevor Lambkin
How Torres Strait Island butterflies could help conservation efforts

A University of Queensland researcher has spent decades compiling a first-of-its-kind database of the butterfly species of the Torres Strait Islands, boosting biosecurity and conservation measures in the region.

Dr Trevor Lambkin working in the field in Torres Strait.
Working closely with the Torres Strait Island Regional Council, Dr Trevor Lambkin said the database, listing 227 butterfly species will help local officials address the impacts of climate change, other human threats and weeds.

“My work has created detailed checklists and distribution maps of butterfly populations on each island for the first time, and this specific information will assist in future conservation measures,” Dr Lambkin said.

“As butterflies are prone to move from place to place, they’re very good yardsticks for use in predicting invasions of pest species.”

Dr Lambkin has made more than 30 visits to the islands over the past 38 years, discovering that several species of butterflies are now threatened by rising sea levels, directly linked to climate change.

“The threat of climate change requires urgent and well-directed conservation efforts to slow not only butterfly loss, but wider biodiversity loss,” he said.

One coronavirus vaccine may protect against other coronaviruses

Study is the first to demonstrate cross-protective immunity by vaccines

Northwestern Medicine scientists have shown for the first time that coronavirus vaccines and prior coronavirus infections can provide broad immunity against other, similar coronaviruses. The findings build a rationale for universal coronavirus vaccines that could prove useful in the face of future epidemics.

“Until our study, what hasn’t been clear is if you get exposed to one coronavirus, could you have cross-protection across other coronaviruses? And we showed that is the case,” said lead author Pablo Penaloza-MacMaster, assistant professor of microbiology-immunology at Northwestern University Feinberg School of Medicine.

The findings were recently published in the Journal of Clinical Investigation.

The three main families of coronaviruses that cause human disease are:

  1. Sarbecovirus, which includes the SARS-CoV-1 strain that was responsible for the 2003 outbreak of Severe Acute Respiratory Syndrome (SARS), as well as SARS-CoV-2, which is responsible for COVID-19
  2. Embecovirus, which includes OC43, which is often responsible for the common cold
  3. Merbecovirus, which is the virus responsible for Middle East Respiratory Syndrome (MERS), first reported in 2012.

Vaccines demonstrated cross-protective immunity

Plasma from humans who had been vaccinated against SARS-CoV-2 produced antibodies that were cross-reactive (potentially providing protection) against SARS-CoV-1 and the common cold coronavirus (OC43), the study found. The study also found mice immunized with a SARS-CoV-1 vaccine developed in 2004 generated immune responses that protected them from intranasal exposure by SARS-CoV-2. Lastly, the study found prior coronavirus infections can protect against subsequent infections with other coronaviruses.

Scientists find evidence the early solar system harbored a gap between its inner and outer regions

An MIT study suggests that a mysterious gap existed within the solar system’s protoplanetary disk around 4.567 billion years ago, and likely shaped the composition of the solar system’s planets. This image shows an artist’s interpretation of a protoplanetary disk.
Credits:Credit: National Science Foundation, A. Khan

In the early solar system, a “protoplanetary disk” of dust and gas rotated around the sun and eventually coalesced into the planets we know today.

A new analysis of ancient meteorites by scientists at MIT and elsewhere suggests that a mysterious gap existed within this disk around 4.567 billion years ago, near the location where the asteroid belt resides today.

The team’s results, appearing today in Science Advances, provide direct evidence for this gap.

“Over the last decade, observations have shown that cavities, gaps, and rings are common in disks around other young stars,” says Benjamin Weiss, professor of planetary sciences in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “These are important but poorly understood signatures of the physical processes by which gas and dust transform into the young sun and planets.”

Likewise the cause of such a gap in our own solar system remains a mystery. One possibility is that Jupiter may have been an influence. As the gas giant took shape, its immense gravitational pull could have pushed gas and dust toward the outskirts, leaving behind a gap in the developing disk.

Contraceptive pill can reduce type 2 diabetes risk in women with polycystic ovary syndrome

A study led by the University of Birmingham has revealed for the first time that the contraceptive pill can reduce the risk of type 2 diabetes by over a quarter in women with polycystic ovary syndrome (PCOS).

The research findings also show that women with PCOS have twice the risk of developing type 2 diabetes or pre-diabetes (dysglycemia) – highlighting the urgent need to find treatments to reduce this risk.

In addition to the risk of type 2 diabetes, PCOS – which affects 10% of women world-wide - is also associated with a number of other conditions in the long-term, such as endometrial cancer, cardiovascular disease, and non-alcohol related fatty liver disease (NAFLD).

Symptoms of PCOS include irregular periods or no periods at all, which can lead to fertility issues, and many suffer from unwanted hair growth (known as ‘hirsutism’) on the face or body, hair loss on the scalp, and oily skin or acne. These symptoms are caused by high levels of hormones called androgens in the blood of women with PCOS.

Women with PCOS also often struggle with weight gain and the cells in their body are often less responsive to insulin – the hormone that allows the body to absorb glucose (blood sugar) into the cells for energy. This reduced response to insulin can lead to elevated blood glucose levels and can cause the body to make more insulin, which in turn causes the body to make more androgens. The androgens further increase insulin levels - driving a vicious circle.

A decade after gene therapy

Evangelina Vaccaro, above, who received the gene therapy
 for ADA-SCID in a clinical trial in 2012.
Credit: Courtesy of Alysia Padilla-Vaccaro
Over a decade ago, UCLA physician-scientists began using a pioneering gene therapy they developed to treat children born with a rare and deadly immune system disorder. They now report that the effects of the therapy appear to be long-lasting, with 90% of patients who received the treatment eight to 11 years ago still disease-free.

ADA-SCID, or adenosine deaminase–deficient severe combined immunodeficiency, is caused by mutations in the gene that creates the ADA enzyme, which is essential to a functioning immune system. For babies with the disease, exposure to everyday germs can be fatal, and if untreated, most will die within the first two years of life.

In the gene therapy approach detailed in the new paper, Dr. Donald Kohn of UCLA and his colleagues removed blood-forming stem cells from each child’s bone marrow, then used a specially modified virus, originally isolated from mice, to guide healthy copies of the ADA gene into the stem cells’ DNA. Finally, they transplanted the cells back into the children’s bone marrow. The therapy, when successful, prompts the body to produce a continuous supply of healthy immune cells capable of fighting infections. Because the transplanted stem cells are the baby’s own, there is no risk of rejection.

Thursday, October 14, 2021

New technique, effective in mice, could help advance the use of probiotics

Quanyin Hu
Scientists studying probiotics, beneficial bacteria that show promise for their ability to treat inflammatory bowel disease and other intestinal disorders, continue to face a problem: how to keep probiotics from getting obliterated in the gut before they can be helpful.

Researchers at the University of Wisconsin–Madison School of Pharmacy think they have a solution involving a dual-layer protection system that can keep probiotic bacteria alive in the lower intestine long enough to help treat or prevent colitis in a mouse model of the disease.

Quanyin Hu and postdoctoral researcher Jun Liu have filed for a patent on their double-protection technique and, with their collaborators, published their findings in the journal Nano Today.

If the new technique shows similar effectiveness in clinical trials, it could help advance the use of probiotics.

The research addresses one of the biggest limitations of treating disease with probiotics, which are bacteria that promote healthy tissue development and improve the gut microbiome.

“When you transfer these bacteria through the oral route, most of them are getting killed by the acidic environment of the stomach. Or they’re getting cleared out of the intestine because they aren’t adhering,” says Hu, the senior author of the report. “Our double protection technique addresses these limitations.”

Gel fights drug-resistant bacteria

In the fight against multidrug-resistant bacteria, scientists in Sweden have developed a new kind of antibiotic-free protection for wounds that kills drug-resistant bacteria and induces the body’s own immune responses to fight infections.

Reporting in the Journal of the American Chemical Society, researchers from KTH Royal Institute of Technology, Karolinska Institutet and Karolinska University Hospital say that the new treatment is based on specially-developed hydrogels consisting of polymers known as dendritic macromolecules.

KTH Professor Michael Malkoch says the hydrogels are formed spontaneously when sprayed on wounds and 100 percent degradable and non-toxic.

“Dendritic hydrogels are excellent for wound dressing materials because of their soft, adhesive and pliable tactile properties, which provide ideal contact on the skin and maintain the moist environment beneficial for optimal wound healing,” he says.

Before and after. On the left, bacteria prior to exposure to the dendritic hydrogel, and on the right, the bacteria is visibly damaged.

The antibacterial effects of the hydrogels have yet to be fully understood, but the key lies in these macromolecules’ structure. It’s distinguished by well-ordered branches that terminate with a profusion of cationic, charged contact points.

How T cell assassins reload their weapons to kill and kill again

Cytotoxic T cells are specialist white blood cells that are trained by our immune system to recognize and eliminate threats – including tumor cells and cells infected with invading viruses, such as SARS-CoV-2, which causes COVID-19. They are also at the heart of new immunotherapies that promise to transform cancer treatment.

Professor Gillian Griffiths from the Cambridge Institute for Medical Research, who led the research, said: “T cells are trained assassins that are sent on their deadly missions by the immune system. There are billions of them in our blood, each engaged in a ferocious and unrelenting battle to keep us healthy.

“Once a T cell has found its target, it binds to it and releases its toxic cargo. But what is particularly remarkable is that they are then able to go on to kill and kill again. Only now, thanks to state-of-the-art technologies, have we been able to find out how they reload their weapons.”

Covid Lockdown: children who spent more time in nature fared best

Credit: Ben Wicks on Unsplash
A study has found that children who increased their connection to nature during the first COVID-19 lockdown were likely to have lower levels of behavioral and emotional problems, compared to those whose connection to nature stayed the same or decreased - regardless of their socio-economic status.

The study, by researchers at the University of Cambridge and the University of Sussex, also found that children from affluent families tended to have increased their connection to nature during the pandemic more than their less affluent peers.

Nearly two thirds of parents reported a change in their child’s connection to nature during lockdown, while a third of children whose connection to nature decreased displayed increased problems of wellbeing - either through ‘acting out’ or by increased sadness or anxiety.

The results strengthen the case for nature as a low-cost method of mental health support for children, and suggest that more effort should be made to support children in connecting with nature - both at home and at school.

The researchers’ suggestions for achieving this include: reducing the number of structured extracurricular activities for children to allow for more time outside, provision of gardening projects in schools, and funding for schools, particularly in disadvantaged areas, to implement nature-based learning programs.

Pesticide linked to chronic kidney disease

A commonly available pesticide has been associated with an increased risk of chronic kidney disease (CKD) in a University of Queensland study.

Researchers analyzed links between pesticide exposure and the risk of kidney dysfunction in 41,847 people, using data from the USA National Health and Nutrition Examination Survey (NHANES).

School of Public Health Associate Professor, Nicholas Osborne said the study found people exposed to higher amounts of the insecticide Malathion, known as Maldison in Australia, had 25 per cent higher risk of kidney dysfunction.

“Nearly one in 10 people in high income countries show signs of CKD, which is permanent kidney damage and loss of renal function,” Dr Osborne said.

Risk factors of developing CKD include age, hypertension and diabetes.

Dr Osborne said CKD with no known cause was rising in low-to-middle income countries such as India, Sri Lanka and Mesoamerica.

“Initially, it was suspected the condition was associated with agricultural workplaces through exposure to heat stress, dehydration, pesticide spraying, heavy metals and agrochemicals,” Dr Osborne said.

Wednesday, October 13, 2021

Identifying Better Ways to Save the World’s Reefs

Scientists work to restore damaged coral reefs by
growing health fragments to transplant.
Photo: University of Konstanz/Anna Rolk.
In the race to save the world’s fragile corals from climate change and disease, USF Department of Integrative Biology Assistant Professor John Parkinson is among an international group of scientists looking for better ways to restore damaged reefs. In new research published Tuesday in the journal Nature Reviews Earth & Environment, the team makes its case for nature-based approaches that give coral colonies a boost in their fight to survive warming seas.

Led by the University of Konstanz in Germany, the team calls for the use of new technologies to identify, propagate, and even strengthen naturally resilient coral colonies, which can then be transplanted to threatened reefs. The systematic review evaluates several emerging methods that have been used to improve coral heat tolerance, scoring them in terms of risk, cost, and scalability. The objective of the project is to provide guidance on which interventions might most effectively extend the natural adaptive capacity of corals, the researchers said.

The race to save the world’s coral reefs is a high priority for conservationists: 30 percent of all marine biodiversity depends on reef ecosystems and more than one billion people rely on the reefs for sustaining fishing stocks, tourism, and a healthy marine environment. Even a small rise in ocean temperatures can cause coral “bleaching” – when corals expel the algae living in their tissues causing the coral to turn completely white – leaving the organisms more susceptible to disease and death.

Flu season is coming and it could be ugly

Photo by Usman Yousaf on Unsplash
As COVID-19 restrictions ease, Canada is seeing a resurgence of many respiratory viruses—and many experts predict this year’s flu season could be severe.

Dr. Michael Curry (he/him), clinical associate professor with UBC faculty of medicine’s department of emergency medicine, reveals how this year’s flu season will be different from the last and weighs in on how to reduce your risk of getting sick.

How will this year’s flu season be different from last year?

Last flu season we essentially had no cases of influenza and relatively few cases of other respiratory viruses here in Canada. When someone was sick with a respiratory infection eight or nine months ago, it was very likely they had COVID-19.

This year, the big change I have seen is the re-emergence of our ‘usual suspect’ respiratory infections. Common cold viruses are back and circulating again. While we are still seeing COVID-19 in Canada, we are finding other respiratory viruses on a regular basis as well.

How might this year’s flu season interact with the fourth wave of COVID-19?

With the upsurge in other respiratory viruses, we can expect a resurgence of influenza this year.

A bad flu season can rapidly fill up emergency departments and hospital beds, and as we all know, COVID-19 is already doing a good job at that.

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