November in Context
A round-up of some of this month’s most exciting biology news.
As England comes to the end of a second strict national lockdown, and cases showing signs of levelling out, there is a lot of COVID related research to be optimistic about this month. November has seen the announcement of promising results from phase III of three vaccine trials.
Biotech company Moderna reported that their vaccine is more than 94.5% effective at preventing COVID-19 based on only 5 cases in the vaccinated group from a cohort of 25,654 participants. This announcement came shortly after news that the Pfizer and BioNTech vaccine trial saw just 94 cases of COVID-19 from a cohort of 43,538 trial participants, this is much lower than the expected rate of infection in the general population. Interestingly, 42% of participants were reported to have “racially and ethnically diverse backgrounds” which is often missing from such trials.
Soon after this promising news, it was initially reported that a third vaccine candidate from the joint efforts of the University of Oxford and AstraZeneca is 90% effective. However, this 90% efficacy only applies to a small sub-set of participants who had mistakenly received a half-sized dose first, and a full-sized dose second. For most participants, who received two full doses, the vaccine efficacy was much lower, at 62%. It is currently unclear why this is the case.
For all vaccines, there are still several pressing questions that researchers would like to see addressed before vaccines are rolled out to the general public such as:
How long will the effectiveness of the vaccines last?
Are the vaccines just as effective in the elderly population, who are the most effected by coronavirus?
Are the vaccines only effective on those with no or very mild symptoms, or are they effective in more severe cases?
It is important to note that these reports do not come from final and peer-reviewed data, this means that have not been fully scrutinised and may not be completely understood. However, given the urgency of the situation, all companies have requested emergency approval to authorise use of their vaccines. In the UK, the NHS has been told to expect deliveries of the Pfizer-BioNTech vaccine as soon as 7th December, following this emergency regulatory approval. NHS staff are said to be the first in line to receive the vaccine.
How do the vaccines work?
Vaccines are traditionally weakened or inactive fragments of the virus they are fighting against but both the Moderna and Pfizer vaccines are mRNA-based vaccines. When introduced into the body, the genetic material mRNA delivers instructions to our own cells to make and display the “spike proteins” that are on the outside of SARS-CoV2 and would normally allow the virus to enter human cells. The presence of these spike proteins on our cells triggers the immune system and trains it to recognise coronavirus in the future. The Oxford-AstraZeneca vaccine is made from a common-cold causing virus (known as an adenovirus) that was isolated from the stool of chimpanzees and engineered to be inactive. Like the other vaccines, when injected it instructs the body to make the SARS-CoV2 spike proteins and triggers the body’s immune response.
Can hallucinogenic mushrooms treat depression?
A small, preliminary study from the John Hopkins school of medicine, suggests that psilocybin – the active ingredient in hallucinogenic mushrooms- might treat depression more effectively than typical antidepressants for some, if taken in alongside therapy.
In the study, 24 participants with major depressive disorder completed a treatment of two doses of psilocybin and received psychotherapy before, during and after the treatment. Participant’s symptoms were measured with a depression rating scale (GRID-HAMD) that ranges from 0 to 52. Before receiving psilocybin, participants had an average GRID-HAMD score of 22.8, putting them in the severe-moderate level of depression. This was reduced to an average score of 8.5, or mild depression, four weeks after the second dose. Although the study was only conducted on a small group of participants, the large decrease in score suggests the change can be attributed to the drug, rather than participant’s expectations.
Lonely brains crave interaction like food
A new study from MIT has found that the brain activity in social isolation overlaps with that seen in hunger. Participants who had undergone a 10 hour fast showed activity in the substantia nigra in the mid-brain when showed images of food during an MRI scan. This part of the brain has been linked to hunger before and is involved in reward-seeking behaviour. The same group of people underwent 10 hours of social isolation, including no access to social media, and showed activity in the same part of the brain in response to images of people doing activities. Interestingly, participants who reported feeling isolated before the study showed a weaker response following the 10-hour isolation. These findings begin to show that hunger and social cravings work in a very similar way in the brain.
With this information, researchers now hope to look at how the effects of social isolation on the brain might be alleviated, for example through remote social interaction. This seems especially important during international lockdowns causing greater social isolation than ever.
The U.S Food and Drug Association has approved a drug which will be the first treatment for the rare and fatal genetic disorder, progeria. Progeria causes cells to age rapidly and children with the disorder have a life expectancy of around 13 years.
Researchers have developed a fully recyclable, self-repairing, skin-like wearable device that can take the place of wearable fitness devices such as the Fitbit. With a thickness just over that of a plaster, the electronic skin can track steps, measure body temperature, and detect heart rate. However, it currently requires an external power source to work.
The new World Health Organisation (WHO) guidelines of physical activity and sedentary behaviour, last updated in 2010, recommend that all adults should undertake 2.5 – 5 hours of moderate intensity or 75 minutes – 2.5 hours of vigorous intensity physical activity per week to counter the harmful effects caused by prolonged sitting.
By Ella Hubber