New York, June 2 (IANS) China, Japan, Philippines and Thailand may turn into "hotspots" favourable for bats that carry coronaviruses and conditions in these places could become ripe for the disease to jump from bats to humans, finds a new study.The study, published in the journal Nature Food, showed that this is because of the global land-use changes including forest fragmentation, agricultural expansion and concentrated livestock production.Most of the current hot spots are clustered in China, where a growing demand for meat products has driven the expansion of large-scale, industrial livestock farming.Further, parts of Japan, the north Philippines and China south of Shanghai are also at risk of becoming hot spots with further forest fragmentation, while parts of Indochina and Thailand may transition into hot spots with increases in livestock production, according to a team of researchers from the University of California, Berkeley, Polytechnic University of Milan and Massey University of New Zealand."Land use changes can have an important impact on human health, both because we are modifying the environment, but also because they can increase our exposure to zoonotic disease," said Paolo D'Odorico, Professor of environmental science, policy and management at UC Berkeley.While the exact origins of the SARS-CoV-2, virus that caused Covid-19, remain unclear, the disease likely emerged when a virus that infects horseshoe bats was able to jump to humans -- either directly through wildlife-to-human contact, or indirectly by first infecting an intermediate animal host, such as the pangolin.Horseshoe bats are known to carry a variety of coronaviruses, including strains that are genetically similar to ones that cause Covid-19 and SARS."While we are unable to directly trace the transmission of SARS-CoV-2 from wildlife to humans, we do know that the type of land use change that brings humans into the picture is typically associated with the presence of these bats who are known to carry the virus," D'Odorico said.The study used remote sensing to analyse land use patterns throughout the horseshoe bat's range, which extends from Western Europe through Southeast Asia.--IANSrvt/in
New York, May 11 (IANS) US researchers have developed a potential new vaccine, which has proven effective against the original SARS-CoV-1, SARS-CoV-2 as well as its UK, South Africa and Brazil variants and related bat Coronaviruses that could potentially cause the next pandemic.The new vaccine, called pan-coronavirus vaccine, was found effective in protecting monkeys and mice.Pan-coronavirus vaccine triggers neutralising antibodies via a nanoparticle. The nanoparticle is composed of the Coronavirus part that allows it to bind to the body's cell receptors and is formulated with a chemical booster called an adjuvant. Success in primates is highly relevant to humans, said researchers from the Duke University in North Carolina, US.The findings, published in the journal Nature, showed that the nanoparticle vaccine, in monkeys, blocked Covid-19 infection by 100 per cent. The new vaccine also elicited significantly higher neutralising levels in the animals than current vaccine platforms or natural infection in humans."We began this work last spring with the understanding that, like all viruses, mutations would occur in the SARS-CoV-2 virus, which causes Covid-19," said senior author Barton F Haynes, director of the Duke Human Vaccine Institute (DHVI)."The mRNA vaccines were already under development, so we were looking for ways to sustain their efficacy once those variants appeared."This approach not only provided protection against SARS-CoV-2, but the antibodies induced by the vaccine also neutralised variants of concern that originated in the UK, South Africa and Brazil. And the induced antibodies reacted with quite a large panel of coronaviruses," Haynes said.The team built on earlier studies involving SARS, the respiratory illness caused by a coronavirus called SARS-CoV-1. They found a person who had been infected with SARS developed antibodies capable of neutralising multiple coronaviruses, suggesting that a pan-coronavirus might be possible.They identified one particular receptor-binding domain site that is present on SARS-CoV-2, its circulating variants and SARS-related bat viruses that makes them highly vulnerable to cross-neutralising antibodies.The team then designed a nanoparticle displaying this vulnerable spot. The nanoparticle is combined with a small molecule adjuvant, which boosts the body's immune response to fight the disease.--IANSrvt/in
New York - Coronaviruses may be vulnerable to ultrasound vibrations, within the frequencies used in medical diagnostic imaging, said researchers.
Through computer simulations, the team modelled the virus' mechanical response to vibrations across a range of ultrasound frequencies and found that vibrations between 25 and 100 megahertz triggered the virus' shell and spikes to collapse and start to rupture within a fraction of a millisecond.
This effect was seen in simulations of the virus in air and in water, said the researchers, including Tomasz Wierzbicki from Massachusetts Institute of Technology.
"We've proven that under ultrasound excitation the coronavirus shell and spikes will vibrate, and the amplitude of that vibration will be very large, producing strains that could break certain parts of the virus, doing visible damage to the outer shell and possibly invisible damage to the RNA inside," said Wierzbicki.
The coronavirus' structure is an all-too-familiar image, with its densely packed surface receptors resembling a thorny crown, the team said.
These spike-like proteins latch onto healthy cells and trigger the invasion of viral RNA. While the virus' geometry and infection strategy is generally understood, little is known about its physical integrity.
For the study, published in the Journal of the Mechanics and Physics of Solids, the team introduced acoustic vibrations into the simulations and observed how the vibrations rippled through the virus' structure across a range of ultrasound frequencies.
The team started with vibrations of 100 megahertz, or 100 million cycles per second, which they estimated would be the shell's natural vibrating frequency, based on what's known of the virus' physical properties.
When they exposed the virus to 100 MHz ultrasound excitations, the virus' natural vibrations were initially undetectable. But within a fraction of a millisecond the external vibrations, resonating with the frequency of the virus' natural oscillations, caused the shell and spikes to buckle inward, similar to a ball that dimples as it bounces off the ground.
As the researchers increased the amplitude, or intensity, of the vibrations, the shell could fracture -- an acoustic phenomenon known as resonance that also explains how opera singers can crack a wineglass if they sing at just the right pitch and volume.
At lower frequencies of 25 MHz and 50 MHz, the virus buckled and fractured even faster, both in simulated environments of air, and of water that is similar in density to fluids in the body. (IANS)
New York- Researchers have uncovered a potential new way to target pancreatic tumours that express high intratumooural interferon signalling (IFN).
The team found that high type I IFN signalling is present in a subset of pancreatic tumours and it triggers a decrease in the level of nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide hydrogen (NADH) in pancreatic cancer cells, which are vital cofactors in critical metabolic processes.
"This is a study that identifies a potential vulnerability created by type I IFNs in pancreatic cancer that can be leveraged for what appears to be an effective therapeutic strategy," said researcher Timothy Donahue from the University of California - Los Angeles, in a mice-based study.
After the researchers delineated the mechanism by which the NAD depletion occurs, they demonstrated that cells with high IFN signalling were more sensitive to Nicotinamide phosphoribosyltransferase (NAMPT) inhibitors, which inhibit a major pathway in NAD synthesis.
Based on this mechanism, recently developed second-generation NAMPT inhibitors could potentially be used in combination with new systemic drugs, called STING agonists, which increase type I IFN signalling, according to a paper published in the Proceedings of the National Academy of Sciences .
When tested in mice, the combination of IFN signalling and NAMPT inhibitors not only decreased pancreatic tumour growth, but also resulted in fewer liver metastases.
"With the advent of these two new and improved therapeutics, our findings are timely as their combination may sensitize tumours to NAD depletion," said lead author Alexandra Moore from the varsity.
The findings provide evidence that if tumours with high IFN signaling can be identified, or if IFN signalling can be amplified in tumour cells, those tumours may have greater sensitivity to treatment with NAMPT inhibitors. If so, the combination could potentially help improve the prognosis for one of the most difficult cancers to treat, the team said. (IANS)
London - Researchers have found coronaviruses closely related to SARS-CoV-2, the virus responsible for the Covid-19 pandemic, in bats stored in laboratory freezers in Cambodia and Japan, according to a study published in the journal Nature.
The virus in Cambodia was discovered in two Shamel's horseshoe bats stored in a freezer, which were captured in the north of the country in 2010.
Meanwhile, a team in Japan found another closely related coronavirus in frozen bat droppings, the study showed.
"The viruses are the first known relatives of SARS-CoV-2 to be found outside China," said the study, noting that the new findings support the World Health Organisation's search across Asia to investigate the animal origin of the COVID-19 pandemic.
But whether the new coronavirus SARS-CoV-2 passed directly from bats to people or through an intermediate host still remains unknown, reports Xinhua news agency.
"Both discoveries are exciting because they confirm that viruses closely related to SARS-CoV-2 are relatively common in Rhinolophus bats, and even in bats found outside China," Alice Latinne, an evolutionary biologist at the Wildlife Conservation Society Vietnam in Hanoi, who has seen some of the Cambodian team's analysis, was quoted as saying.
Aaron Irving, an infectious-diseases researcher at Zhejiang University in China's Hangzhou, who also plans to test stored samples of bats and other mammals, said the findings suggest that other "as-yet undiscovered SARS-CoV-2 relatives" could be stored in lab freezers, it added. (IANS)
New York, Oct 28 (IANS) Researchers have revealed that coronaviruses are adept at imitating human immune proteins that have been implicated in severe Covid-19 disease.According to the study, published in the journal Cell Systems, many plants and animals use the art of mimicry to trick their prey or predators.Viruses employ a similar strategy: Viral proteins can mimic the three-dimensional shapes of their host's proteins to trick the host into helping the virus complete its life cycle."Viruses use mimicry for the same reason as plants and animals -- deception," said study author Sagi Shapira from Columbia University Vagelos College of Physicians and Surgeons in the US."We hypothesized that identifying viral-protein lookalikes would give us clues to the way viruses, including SARS-CoV-2, cause disease," Shapira added.In the study, the research team used supercomputers to search for viral mimics with a programme similar to 3D facial recognition software. They scanned more than 7,000 viruses and over 4,000 hosts across the Earth's ecosystems and uncovered six million instances of viral mimicry."Mimicry is a more pervasive strategy among viruses than we ever imagined," Shapira said.It's used by all kinds of viruses, regardless of the size of the viral genome, how the virus replicates, or whether the virus infects bacteria, plants, insects or people.But some types of viruses used mimicry more than others. Papilloma and retroviruses, not so much.Coronaviruses, on the other hand, are particularly good at it and were found to mimic over 150 proteins, including many that control blood coagulation or activate complement -- a set of immune proteins that help target pathogens for destruction and increase inflammation in the body."We thought that by mimicking the body's immune complement and coagulation proteins, coronaviruses may drive these systems into a hyperactive state and cause the pathology we see in infected patients," Shapira said.Over the course of the pandemic, it has become clear that many Covid-19 patients have coagulation problems and some are now treated with anti-coagulants and drugs that limit complement activation.In a separate paper published in the journal Nature Medicine, the Columbia researchers found evidence that functional and genetic dysregulation in immune complement and coagulation proteins are associated with severe Covid-19 disease. --IANSbu/bg