Progeria: New treatment could extend lives of children with 'premature aging' syndrome
The new treatment targets the underlying genetic cause of the disease.
- Progeria is an "accelerated aging" disease that causes children to die of "old age" at around 13 to 15 years.
- There are only two existing treatments, and both have unpleasant side effects.
- A promising new therapy based on biotechnology increases the lifespan of mice by over 60% and is ready for human clinical trials.
Johnson & Johnson COVID-19 vaccine authorized: Here's what makes it unique
Millions of doses of Johnson & Johnson's COVID-19 vaccine could be distributed as early as this week.
- The FDA and CDC recently authorized the distribution of Johnson & Johnson's COVID-19 vaccine.
- It will soon be the third vaccine available in the U.S., the other two being vaccines produced by Pfizer-BioNTech and Moderna.
- The new vaccine has a lower efficacy rate, but clinical data suggest its highly effective at preventing hospitalization and death.
Credit: Mediteraneo via Adobe Stock
<p>What makes Johnson & Johnson's vaccine unique is that it's effective after just one dose, while the vaccines produced by Pfizer-BioNTech and Moderna require two doses administered over several weeks.</p><p>And unlike the other two vaccines, Johnson & Johnson's vaccine doesn't need to be frozen during shipping and storage, it just needs to be refrigerated. That's because the vaccine protects against COVID-19 by delivering coronavirus proteins to the body through a common cold virus known as adenovirus type 26. In contrast, the other two vaccines perform a similar function, but they do it through mRNA, which is more delicate and requires freezing.</p><p>Not having to freeze the single-shot vaccine will make it cheaper and easier to distribute across the country, and it could result in many more people getting vaccinated.</p><p>But it's worth noting that Johnson & Johnson's vaccine doesn't seem to be as effective as the other two vaccines. According to the FDA analysis, the vaccine is about 66 percent effective at preventing moderate to severe cases of COVID-19, "when considering cases occurring at least 28 days after vaccination." Meanwhile, clinical data show that the Pfizer-BioNTech and Moderna vaccines are about 95 percent effective at preventing severe cases of the disease.</p>Credit: peterschreiber.media via Adobe Stock
<p>Still, that doesn't necessarily mean Johnson & Johnson's vaccine is inferior. The FDA analysis found that nobody who received the Johnson & Johnson vaccine was hospitalized or died due to COVID-19 (at least among cases that occurred 28 days after getting the shot).</p><p>So, while some people who receive the Johnson & Johnson vaccine may still contract coronavirus, the vaccine does seem to significantly reduce the severity of COVID-19. The same holds true for the other two vaccines: Getting the shot (or shots) won't completely protect you from the virus, but it does protect you from the disease, reducing the chances of becoming hospitalized or dying to almost zero.</p>COVID-19 vaccines and transmission
<p>But what's less clear is the extent to which the vaccines prevent the spread of the novel coronavirus. Because the vaccines don't completely protect against infection, it might be possible for a vaccinated person to spread the virus. But COVID-19 vaccines might make transmission less likely.</p><p>After all, even if a person who gets vaccinated contracts the coronavirus, the virus would have a harder time replicating in their body, because the vaccine bolsters the immune response. So, one would expect that person to "shed" less of the virus out of their mouth and nose. In short: fewer infections means less replication, less shedding, and less transmission. </p><p>That's the theory, anyway.</p><p><span></span>Scientists are still working to understand how exactly these vaccines affect transmission. But early data is promising. In a <a href="https://www.medrxiv.org/content/10.1101/2021.02.06.21251283v1.full-text" target="_blank">preprint paper published on medRxiv</a>, Israeli researchers measured the amount of coronavirus within about 2,900 people who had received the Pfizer-BioNTech vaccine.</p><p style="margin-left: 20px;">"Analyzing positive SARS-CoV-2 test results following inoculation with the BNT162b2 mRNA vaccine [the Pfizer vaccine], we find that the viral load is reduced four-fold for infections occurring 12-28 days after the first dose of vaccine," the paper said. "These reduced viral loads hint to lower infectiousness, further contributing to vaccine impact on virus spread."</p><p>But until the data on vaccines and transmission become clear, the CDC recommends that vaccinated people still wear masks and practice social distancing.<br><br><strong>UPDATE:</strong> The CDC voted on Sunday to recommend the vaccine for the United States. CDC Director Dr. Rochelle Walensky signed off on the recommendation.</p>Toward a disease-sniffing device that rivals a dog’s nose
Trained dogs can detect cancer and other diseases by smell. Could a device do the same?
Numerous studies have shown that trained dogs can detect many kinds of disease — including lung, breast, ovarian, bladder, and prostate cancers, and possibly Covid-19 — simply through smell. In some cases, involving prostate cancer for example, the dogs had a 99 percent success rate in detecting the disease by sniffing patients' urine samples.
New study identifies 126 species that could host coronavirus
The study suggests scientists are underestimating the number of animal species that could generate the next novel coronavirus.
- The novel coronavirus that causes COVID-19 is a product of different coronaviruses recombining in animal species.
- A new study suggests that hundreds of animal species may harbor multiple types of coronaviruses, meaning recombination events could be more likely than previously thought.
- The authors noted that their results could help improve surveillance programs to mitigate the risks associated with a future novel coronavirus.
Wardeh et al.
<p class="caption"><em>Predicted hosts are grouped by order (inner circle). Middle circle presents probability of association between host and SARS-CoV-2 (grey scale indicates predicted associations with probability in range > 0.5 to ≤0.75. Red scale indicates predicted associations with probability in range > 0.75 to <0.9821. Blue to purple scale present indicates associations with probability ≥ 0.9821). Yellow bars represent number of coronaviruses (species or strains) observed to be found in each host. Blue stacked bars represent other coronaviruses predicted to be found in each host by our model. Predicted coronaviruses per host are grouped by prediction probability into three categories (from inside to outside): ≥0.9821, >0.75 to <0.9821 and >0.5 to ≤0.75.<br></em><br>To answer that, the researchers behind the recent study created a computer model to predict which species have the highest risk of being "reservoirs" for coronaviruses. Using data from GenBank, a National Institutes of Health database, the team compared 411 coronaviruses with 876 mammalian species that are known to contract coronaviruses.</p><p>The model predicted that each coronavirus species can infect, on average, more than 12 types of mammalian hosts. Meanwhile, the results suggested that each mammalian host can contract roughly five different types of coronavirus.</p><p>In terms of recombination, some mammalian species pose outsized threats. The study noted that the domestic pig presents a high risk because it is known to harbor many diverse coronaviruses.</p><p style="margin-left: 20px;">"Given the large number of predicted viral associations presented here, the pig's close association to humans, its known reservoir status for many other zoonotic viruses, and its involvement in genetic recombination of some of these viruses, the pig is predicted to be one of the foremost candidates an important recombination host," the authors wrote.</p>Credit: Pixabay
<p>The study also identified species in which SARS-CoV-2 might combine with other coronaviruses. These included the lesser Asiatic yellow bat, the common hedgehog, the European rabbit, chimpanzees, the African green monkey and domestic cats (which are already known to contract SARS-CoV-2, though there's no evidence that cats or other pets can spread the novel coronavirus to humans).<br></p><p>Also on that list was the dromedary camel, a "known host of multiple coronaviruses and the primary route of transmission of MERS-CoV to humans." It'd be especially concerning if MERS-CoV and SARS-CoV-2 recombined, considering the former is highly deadly and the latter is highly contagious.</p>Improved surveillance programs
<p>Still, many factors must align for coronaviruses to merge and generate a novel coronavirus, and just because an animal is vulnerable to multiple viruses doesn't mean those viruses will recombine. But the team behind the study noted that scientists are likely underestimating the number of animals that could generate novel coronaviruses, and that the results can help inform surveillance programs for at-risk species.</p><p style="margin-left: 20px;">"Such information could help inform prevention and mitigation strategies and provide a vital early warning system for future novel coronaviruses," the authors wrote.</p>Catnip is for both pleasure and protection, according to a new study
The main bioactive compound in catnip seems to protect cats from mosquitoes. It might protect humans, too.
- For centuries, humans have observed that cats exhibit strange behaviors when exposed to catnip and silver vine.
- A new study examined how the main bioactive compound in these plants affects cats' opioid systems and protects them against mosquito bites.
- The findings suggest that the compound nepetalactol could be used to develop new mosquito repellents for humans.
Nepeta cataria, commonly known as catnip
Credit: Johann Georg Sturm (Painter: Jacob Sturm) via WikiPedia/Public Domain
<p>In the study, researchers from Iwate University in Japan exposed nepetalactol-laced paper to different types of felids, including domestic and feral cats, a leopard, two jaguars, and two lynx. The team also exposed nepetalactol to dogs and mice, but only the cats elicited the expected behavioral response.</p><p>To find out why cats react uniquely to nepetalactol, the researchers measured the animals' endorphin levels before and after they were exposed to the substance. The results showed that nepetalactol raised endorphin levels in cats.</p><p>But when cats were given drugs that blocked opioid receptors, their endorphin levels didn't rise, and their behavior didn't change. This suggests that cats' "μ-opioid system is stimulated by an increase in endogenous β-endorphin secretion when olfactory neurons are activated by these iridoids," the team wrote.</p>Nepetalactol as a mosquito repellent
<p>To test the efficacy of nepetalactol as a mosquito repellant, the researchers anesthetized two groups of cats. For one group, the researchers applied nepetalactol to the cats' heads. The other group was left untreated to serve as a control. The researchers then exposed the cats to Asian tiger mosquitos and counted the number of times the insects bit each group.</p><p>The results showed that the group treated with nepetalactol was much less likely to get bitten, sometimes by as much as 50 percent. The same proved true in a "more natural" experiment, in which cats were allowed to rub their faces on the plants themselves.</p><p style="margin-left: 20px;">"This is convincing evidence that the characteristic rubbing and rolling response functions to transfer plant chemicals that provide mosquito repellency to cats," the team wrote.</p>The world's deadliest animal
<p>While the researchers don't fully understand why nepetalactol activates the μ-opioid system in cats, they think the compound could help humans avoid mosquito bites. After all, some of the study contributors have applied for a patent covering the use of nepetalactol as an insect repellent. Gizmodo <a href="https://gizmodo.com/cats-love-catnip-because-it-protects-them-from-mosquito-1846092518" target="_blank" rel="noopener noreferrer">reports</a> that the researchers even tried applying the compound to their arms, which seemed to prevent mosquito bites.</p><p>For thousands of years, humans have aimed to protect themselves from mosquitos. The Egyptian queen Cleopatra was said to sleep surrounded by a mosquito net. The Romans used vinegar mixtures. And Mississippians turned to the American beautyberry plant. </p><p>Today, DEET is the most widely used mosquito repellent, but it's slightly toxic and can cause side effects, including seizures, though rarely. Developing better mosquito repellents could save many lives. The World Mosquito Program <a href="https://www.worldmosquitoprogram.org/en/learn/mosquito-borne-diseases#:~:text=Nearly%20700%20million%20people%20contract,more%20than%20one%20million%20deaths." target="_blank">reports</a> that mosquito-borne illnesses like malaria and yellow fever affect more than 700 million annually and kill approximately one million. </p>