For the first time, one of the many COVID-19 vaccines in development has protected an animal, rhesus macaques, from the new coronavirus. The vaccine, an old-fashioned formulation consisting of a chemically inactivated version of the virus, produced no obvious side effects in the monkeys; human trials began on 16 April. And encouraging monkey results for other vaccines are close behind.
Researchers from Sinovac Biotech, a privately held Beijing-based company, gave two different doses of their COVID-19 vaccine to a total of eight rhesus macaques. Three weeks later, the group introduced SARS-CoV-2, the virus that causes COVID-19, into the monkeys' lungs. None developed a full-blown infection, and the monkeys given the highest dose of vaccine had the best response: Seven days after the animals received the virus, researchers could not detect it in their pharynx or lungs. Some of the lower dosed animals had a “viral blip” but also appeared to have controlled the infection, the Sinovac team reports in a paper published on 19 April on the preprint server bioRxiv.
In contrast, four control animals developed high levels of viral RNA and severe pneumonia. The results “give us a lot of confidence” that the vaccine will work in humans, says Meng Weining, Sinovac's senior director for overseas regulatory affairs.
“This is old school but it might work. What I like most is that many vaccine producers, also in lower–middle-income countries, could make such a vaccine,” says Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai.
But Douglas Reed of the University of Pittsburgh, who is developing and testing COVID-19 vaccines in monkeys, says the number of animals was too small to yield statistically significant results. In a manuscript in preparation, his team also raises concerns about the way the Sinovac team grew the stock of novel coronavirus used to challenge the animals, which may have evolved differences from the strains that infect humans. What's more, the monkeys are not a perfect model for COVID-19 as they don't develop some symptoms that kill many humans.
The study did address worries that partial protection by a vaccine could be dangerous. Earlier animal experiments with vaccines against the related coronaviruses that cause severe acute respiratory syndrome and Middle East respiratory syndrome had found that low antibody levels could lead to aberrant immune responses, enhancing the infection and damaging their lungs. But the Sinovac team did not find any evidence of lung damage in vaccinated animals that produced relatively low levels of antibodies, which “lessens the concern about vaccine enhancement,” Reed says. “More work needs to be done, though.”
To check the possibility that SARS-CoV-2 variants might thwart a vaccine, the Sinovac researchers mixed antibodies taken from monkeys, rats, and mice given their vaccine with strains of the virus isolated from patients in China, Italy, Switzerland, Spain, and the United Kingdom. The antibodies potently “neutralized” all the strains, which are “widely scattered on the phylogenic tree,” the researchers noted.
“This provides strong evidence that the virus is not mutating in a way that would make it resistant to a #COVID19 vaccine,” tweeted immunologist Mark Slifka of Oregon Health & Science University. “Good to know.”
An experimental vaccine made by the University of Oxford has also shown promise, although the data have not yet been published. Vincent Munster and his team at the Rocky Mountain Laboratories gave six monkeys the vaccine, which contains a gene for the surface protein of SARS-CoV-2 stitched into a harmless adenovirus that infects chimpanzees. Four weeks later, the researchers challenged the vaccinated animals and six controls. Seven days later, the vaccinated animals had a much stronger reduction of virus in their lower respiratory tracts than the controls. “The preliminary results look promising,” Munster says. “People just have to be patient.”
Sinovac recently started phase I human trials of its vaccine in Jiangsu province, north of Shanghai, which aim to gauge safety and immune responses in 144 volunteers. The company hopes to start phase II studies by mid-May that will assess the same endpoints but will enroll more than 1000 people.
If all goes well, Meng says, Sinovac will launch phase III efficacy trials that compare the vaccine with a placebo in thousands of people. Because of the low level of transmission now occurring in China, the company may run additional trials in harder hit countries. “We can't put all our eggs in one basket,” Meng says. Sinovac may also ask regulatory agencies in China and elsewhere for emergency authorization to give the vaccine to those at high risk of becoming infected, such as customs agents and police officers.
According to the World Health Organization, the Oxford vaccine and five others had entered human trials as of 26 April, and 82 candidates were in development. Most use versions of the SARS-CoV-2 surface protein, rather than whole, killed virus. Meng says how a vaccine is made will not ultimately matter. “In this pandemic situation, the most important thing is to make a vaccine, no matter what kind of vaccine it is, that's safe and effective as soon as possible.”
This very restrictive diet is a meat lover’s special.
By Elaine K. Howley, Contributor Sept. 28, 2020, at 1:01 p.m.
This article is based on reporting that features expert sources.
The Carnivore Diet
Humans have evolved the ability to digest all manner of food items, from fruits and vegetables to animal products. Debate continues about what constitutes the best ratio of various types of food to support optimal human health, but a new entrant into the diet scene suggests that all plants are suspect and we should embrace an animal-only diet for improved physical well-being.
Dr. Paul Saladino, an integrative medicine and nutritional biochemistry practitioner in private practice in San Diego and author of “The Carnivore Code: Unlocking the Secrets to Optimal Health by Returning to our Ancestral Diet,” is a staunch proponent of the carnivore diet and says going carnivore is the solution to a range of health issues plaguing humankind. Plants, he says, simply aren’t cutting it.
“If you look at the incidence of chronic disease, no one can deny that in the last 70 years, we’ve become abysmally unhealthy,” Saladino says. “Rates of obesity and overweight are 70% of the U.S. population. Diabetes has gone from 0.9% or 1% to 13% or 14%. And that’s just diagnosed diabetes, not pre-diabetes or metabolic syndrome. Chronic disease now impacts 40% of the population. Fifty or 60 years ago it was 10% or 15%. So the question is, what the heck happened?”
He continues, noting that we’re drinking less alcohol, smoking less and exercising more, and yet we still get sicker. “Unhealthy behaviors have gone way down. And if you look at the number of people who are eating ‘healthfully,’ that’s gone way up. But that’s just according to the U.S. dietary guidelines.”
What’s happening is a good question, and according to Saladino, the answer is that “we’re doing some things that are incompatible with our genetics and evolutionary history that are causing us to get sick.” Namely, eating plants. “Having more vegetables and eating less red meat, we’re getting sicker and sicker.”
He notes that red meat bears the blame for many ailments and chronic diseases, and he thinks this is backward. Plants, he says, are varying levels of toxic to humans, hence why so many of them are poisonous and even some of the ones we can eat, such as beans, must first be must be carefully prepared and cooked to remove toxic proteins. “It’s not a question of if plants are toxic, it’s a question of how toxic any one plant is and how well any individual or animal can detoxify what’s in there,” he says.
By contrast, he notes that “animals don’t have toxins in their body with a few rare exceptions of a small frog in the Amazon and puffer fish liver. But generally speaking, 99.9% of animal organs are all edible by humans. And in fact, it’s incredibly nutritious food and basically what we’ve been thriving on for two to four million years.”
The Carnivore Diet
For meat eaters who are interested in trying the carnivore approach to eating, you’ll have to cut out all plant foods. Yes, really. The goal is to eliminate all carbohydrates, and Saladino says that save for the odd berry or other seasonal fruit our carnivore ancestors would pick up while hunting game, plants are not on the menu.
“It works as an elimination diet by slowly reducing intake of carbohydrates and plant-based food items and increasing intake of animal protein,” Zammit explains. “Oftentimes on an elimination diet, food items may be slowly reintroduced, but that’s not the case here. The ultimate goal is 100% intake of animal-based protein.”
Followers of the diet are instructed to eat any kind of meat and meat product, from fatty cuts of beef, lamb, pork and organ meats, as well as poultry, fish, eggs and dairy products. “Think a 4-ounce ribeye, two eggs and bacon cooked in butter for breakfast, 3 ounces of salmon and 6 ounces of shrimp for lunch. Then 2 ounces of liver and 8 ounces of filet for dinner. There’s no flexibility for a bun on your burger or a piece of fruit for dessert,” Zammit says.
The reason for this very restrictive emphasis on animal protein is simple, Saladino explains. “Animal meat and organs are the most nutrient-rich and bioavailable foods on the planet. They’ve been incredibly vilified for the last 60 years, but they’re an integral part of every healthy human diet.”
It's true that organ meats are highly nutritious, being rich sources of B vitamins, several minerals including iron, magnesium and zinc, and fat-soluble vitamins including vitamins A, D, E and K. Organ meat and animal meat in general contain high levels of protein. And it's true that our hunter-gatherer ancestors ate every part of the animals they hunted, nose to tail.
The idea with this approach is to be as animal-based as possible, as opposed to plant-based. Plant-based diets such as the Mediterranean diet have long been favored by most dietitians and doctors as the healthiest and most sustainable way for humans to eat for longevity and wellness. But the carnivore diet turns that conventional and well-established advice on its head.
Saladino claims that the carnivore diet can be the source of healing for virtually any autoimmune or chronic disease you might be experiencing, from depression and rheumatoid arthritis to diabetes, acne and obesity.
While the diet is extreme, it may result in weight loss. Because the diet is high in fat, it will “promote meal satiety,” meaning that “you’ll feel fuller longer,” Zammit says, which can lead to weight loss. “Feeling satiated from consuming these food items can help reduce your caloric intake, as you won’t feel as hungry, likely leading to weight loss.”
There’s also some evidence that suggests excessive sugar intake can alter brain chemistry, which could contribute to the development of depression. Cutting back on sugar and processed carbs may improve mood, as has been observed with the keto diet in some studies. As an extreme form of keto, there’s an argument to be made that the carnivore diet might also confer some mood-boosting benefits.
Reducing your intake of carbohydrates may also help with blood glucose control, which may be helpful for people with diabetes. Some studies have also noted that the keto diet can reduce inflammation in the brain and body, which may also help with diabetes and other chronic medical conditions.
Zammit also notes that for some people with irritable bowel syndrome or inflammatory bowel disease, symptoms such as bloating and flatulence may also decline because you’ll be consuming far fewer FODMAPs, a type of carbohydrate that can cause gastrointestinal distress in some people.
Saladino says there’s lots of scientific research to back up claims about the superiority of the carnivore diet, but Zammit cautions against confusing anecdotal support with scientific understanding. “This diet demonizes plant-based foods, such as fruits, vegetables, whole grains, beans, lentils, nuts and seeds, while promoting claims of improving fatigue, digestion and autoimmune diseases,” Zammit explains. “These claims are not based on sound science, but rather anecdotal reports.”
Eliminating all food groups from your diet except one is not a risk-free endeavor. As such, Zammit says “there’s a lot to unfold here. But since I’m an oncology dietitian, let’s start with cancer risk.”
It’s long been established that plant-based diets may help ward off cancer. “We have strong evidence from several meta-analytical studies that demonstrate a plant-based diet can greatly reduce your risk of several cancer types, as well as other disease states, including cardiovascular disease and diabetes,” Zammit says.
Similarly, “it’s well-known that a diet heavy in red and processed meats can increase risk of stomach and colorectal cancer. We also know that a diet rich in saturated fat can increase risk of liver cancer,” Zammit explains.
Another potential concern with the carnivore diet is the risk of developing non-alcoholic fatty liver disease, “which is caused by the accumulation of saturated fat. This isn’t always reversible by changing your diet,” Zammit says. “When we have this buildup of saturated fat, it can cause inflammation of the liver, increasing the risk of liver cancer.
Beyond cancer risk, people with heart issues should also use caution when considering a carnivore diet. “If you have a personal or family history of cardiovascular disease and hyperlipidemia, the carnivore diet is not for you,” Zammit says.
The diet is also a poor choice for people with chronic kidney disease, even if they aren’t on dialysis. “With chronic kidney disease, you’re instructed to actually limit your protein intake,” she explains.
“The average protein needs of a healthy individual are 40 to 65 grams per day. When you have CKD, your kidneys no longer have the ability to remove protein wastes, which will then buildup in the blood and can cause a whole host of unpleasant symptoms, including nausea and vomiting, decreased appetite and weakness,” Zammit says.
Because the carnivore diet is bereft of all plant matter, you won’t be taking in much or any fiber. “Due to the lack of fiber, most people will end up with constipation,” Zammit says. (For his part, Saladnio says humans don’t need fiber, and he calls it “one of the greatest cons ever foisted upon humans.” He says we don’t need fiber to digest animal products, and it causes more GI distress than it alleviates.)
“There’s also an increased risk of malnourishment, since you would no longer be consuming a balanced diet,” Zammit says. In particular, “vitamin C would be lacking, increasing risk of scurvy,” a disease that was common among sailors in the 18th century and causes swollen and bleeding gums, anemia, loss of teeth, weakness and poor healing of wounds. It can be deadly.
“In addition to all the medical and nutritional issues one may encounter on a carnivore diet, there’s also the psychological aspect of following a restrictive diet,” that you need to consider before you adopt this approach to nutrition, Zammit says. “Following any restrictive diet can often lead to loneliness and social isolation. It can build distrust with yourself, disconnecting the relationship you have with your body and food. All this can affect your quality of life in a negative way, especially if following long term.” As such, if you have a history of eating disorders, you’d be well advised to avoid this diet.
How Much Does It Cost?
Typically, meat products cost more than plant-based foods, and as such, “you may have to shell out more money than you realize to follow this diet,” Zammit says. “Although you won’t be spending money on the food items you used to include, you’ll make up for it and then some by having to purchase animal protein for all your meals.”
This cost is compounded by the fact that the diet encourages only using “grass-fed and ethically-sourced protein, which is very expensive, and not everyone has the privilege to obtain, depending on their neighborhood and socioeconomic status,” she says.
Diet and Health
Lastly, Zammit notes, it’s important to “keep in mind, that when it comes to your overall health, diet is just one piece of the puzzle. Genetics, age and gender play a huge role in how your body reacts to certain food items or diets, and this isn’t something we can change.”
She also warns about being careful when comparing yourself to other people. “The human body is incredibly complex. There are no ‘bad’ foods, just bad overall diets. Behavior and lifestyle modification are still the best predictors of your health and happiness. At the end of the day, nourish your body based on your individual needs and preferences.”
She also recommends that if you’re thinking of beginning a particular diet, “please contact your local registered dietitian to help educate and guide you.”
For his part, Saladino, who is a devout follower of the carnivore diet, says he’s never felt better since adopting this lifestyle, and he encourages those who feel the need to make some changes to check it out.
“If you’re kicking ass in every way, shape and form, then don’t change a thing. But if you’re looking to improve body composition, libido, emotional stability, mental clarity, autoimmunity, inflammation, chronic disease, I’m so excited to offer these ideas as a tool for people who might not have considered them because we’re so stuck in this rigid paradigm around plants versus animals. It’s a diet for every homo sapiens person that isn’t thriving.”
A team of physicists and materials scientists from the University of Rochester, the University of Nevada Las Vegas and Intel Corporation has created material that is superconducting at room temperature.
First discovered in 1911, superconductivity gives materials two key properties. Electrical resistance vanishes. And any semblance of a magnetic field is expelled, due to a phenomenon called the Meissner effect.
The magnetic field lines have to pass around the superconducting material, making it possible to levitate such materials.
Powerful superconducting electromagnets are already critical components of maglev trains, magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) machines, particle accelerators and other advanced technologies, including early quantum supercomputers.
But the superconducting materials used in the devices usually work only at extremely low temperatures — lower than any natural temperatures on Earth. This restriction makes them costly to maintain — and too costly to extend to other potential applications.
“The cost to keep these materials at cryogenic temperatures is so high you can’t really get the full benefit of them,” said team leader Dr. Ranga Dias, a researcher in the Department of Mechanical Engineering and the Department of Physics and Astronomy at the University of Rochester.
Previously, the highest temperature for a superconducting material was achieved in 2019 by two teams of researchers led by Max Planck Institute for Chemistry’s Dr. Mikhail Eremets and University of Illinois at Chicago’s Dr. Russell Hemley.
That teams reported superconductivity at 250 to 260 K (minus 23.15 to minus 13.15 degrees Celsius, or minus 9.67 to 8.33 degrees Fahrenheit) using lanthanum superhydride.
In setting the new record, Dr. Dias and his colleagues combined hydrogen with carbon and sulfur to photochemically synthesize simple organic-derived carbonaceous sulfur hydride in a diamond anvil cell.
The carbonaceous sulfur hydride exhibited superconductivity at 287.7 K (14.55 degrees Celsius, or 58.19 degrees Fahrenheit) and a pressure of and a pressure of about 39 million pounds per square inch (psi).
“Because of the limits of low temperature, materials with such extraordinary properties have not quite transformed the world in the way that many might have imagined,” Dr. Dias said.
“However, our discovery will break down these barriers and open the door to many potential applications.”
“We live in a semiconductor society, and with this kind of technology, you can take society into a superconducting society where you’ll never need things like batteries again,” added co-author Dr. Ashkan Salamat, a researcher in the Department of Physics and Astronomy at the University of Nevada Las Vegas.
“The next challenge is finding ways to create the room temperature superconducting materials at lower pressures, so they will be economical to produce in greater volume,” Dr. Dias said.
“In comparison to the millions of pounds of pressure created in diamond anvil cells, the atmospheric pressure of Earth at sea level is about 15 psi.”
The research is described in a paper published this week in the journal Nature.
E. Snider et al. 2020. Room-temperature superconductivity in a carbonaceous sulfur hydride. Nature 586, 373-377; doi: 10.1038/s41586-020-2801-z
This article is based on text provided by the University of Rochester.