A repurposed mouse model can develop symptoms of both severe COVID-19 (lung damage, blood clots, abnormal blood vessels, and death) and also of milder disease, including loss of the sense of smell, according to a recent University of Iowa study published in Nature.
A mass screening programme of 10 million Wuhan residents identified 300 asymptomatic cases in May, but none were infectious - according to a new study. They found no 'viable' virus in the asymptomatic cases and the close contacts of these positive asymptomatic cases did not test positive. But these findings do not show that the virus can't be passed on by asymptomatic carriers. Rather mask-wearing, hand washing, social distancing and lockdown have helped reduce Covid-19 virulence.
Using post-mortem tissue samples, researchers from Charité - Universitätsmedizin Berlin have studied the mechanisms by which the novel coronavirus can reach the brains of patients with COVID-19. The results show that SARS-CoV-2 enters the brain via nerve cells in the olfactory mucosa. For the first time, researchers have been able to produce electron microscope images of intact coronavirus particles inside the olfactory mucosa.
Smell loss is a prominent symptom of Covid-19 and the pandemic is leaving many people with long-term smell loss or smell distortions such as parosmia. Parosmia happens when people experience strange and often unpleasant smell distortions. Instead of smelling lemon you may smell petrol. New research shows that parosmia is associated with a recovery of smell performance among patients who undergo 'smell training' (sniffing at least four different odours twice a day every day for several months).
On a near daily basis, the internet spews out numerous tips and tricks for exercise motivation. Now we can add smell to the long and growing list. A research team led by a scientist at the University of California, Riverside, has found olfaction--or smell--may play an important role in motivating mammals to engage in voluntary exercise. Performed in lab mice, the study may open up new areas of research and have relevance for humans.
Meeting a 100-year-old challenge could lead the way to digital aromas
The tongue helps people taste food, but structures on its surface also help them sense textures -- something that's also very important when savoring a meal. Now, researchers reporting in ACS Applied Materials & Interfaces have made a 3D silicone surface that, for the first time, closely mimics the surface features of the human tongue. The material could help food scientists study mechanical interactions of foods, liquids and medicines with the organ.
Scientists led by NTU Singapore have invented an artificial olfactory system that mimics the mammalian nose to assess the freshness of meat accurately. The 'electronic nose' comprises a 'barcode' that changes colour over time in reaction to the gases produced by meat as it decays, and a barcode 'reader' in the form of a smartphone app powered by artificial intelligence.
Problems with the sense of smell appear to be an early indicator of cognitive decline in people with type 2 diabetes. However, it's unknown whether factors such as diet and obesity play a role in who develops these symptoms. Now, researchers reporting in ACS Chemical Neuroscience found that mice fed a moderate-fat, high-sugar chow (simulating a Western diet) showed a faster decline in their ability to learn and remember new odors.
When startled, do all fish respond the same way? A few fish, like Mexican cavefish, have evolved in unique environments without any predators. To see how this lack of predation impacts escape responses that are highly stereotyped across fish species, scientists explored this tiny fish to determine if there are evolved differences in them. Findings reveal that the dramatic ecological differences between cave and river environments contribute to differences in escape behavior in blind cavefish and river-dwelling surface cavefish.