Which came first – chicken or egg: Puzzle solved!

Which came first – chicken or egg? – this is quite a common question as a puzzle. From scientists to sociologists – all had a hard time solving the puzzle because it is impossible to solve this mystery with logic.

This question is actually like a circle, which has no beginning – many have said philosophically in this regard. 

But recently the United States has found a solution to this puzzle. The real truth has been revealed on a website where United States journalist Robert Krulwich has done a lot of research to find out the information about this complex concept. Then the answer matched. The results were published on a US website called NPR.

It has been said that a few thousand years ago, a large bird resembling a chicken lived on the earth. Although the prehistoric bird was genetically very close to the chickens, it was not a ‘chicken’ at all.

Scientists say it was actually a kind of “proto-chicken”. The oldest predecessor of the hen laid an egg. In that egg, the male partner adds several new characteristics. Several more mutations happened - which is quite different from the male or female chicken genes of that time. 

That new species of bird is the origin and real ancestor of today’s chicken. For thousands of years, mutations have changed many times to adapt to the earth.

Today’s chicken may have lots of discrepancies with the first chicken that was created. The mutation occurred in the egg, giving rise to the original hen, meaning that “there was no hen before the egg.” 

In other words, to summarize the whole story, a primitive hen-like bird lays different eggs and gives rise to the primitive hen. So, the eggs came before the chickens mean egg came first and the chicken is later. Source: https://www.daily-bangladesh.com

Read More........→August 06, 2020

Common cold infection may train the body to recognise novel coronavirus: Study

AUG 05, 2020 LOS ANGELES: The immune system's memory helper T cells which recognise the common cold virus and help the body fight it off, also identifies some parts of the novel coronavirus, according to a study whose findings may explain why some people have milder COVID-19 cases than others. The research, published in the journal Science, noted that the immune system''s memory T cells keep track of the viruses they have seen before, giving the cells a headstart in recognising and fighting off repeat invaders. However, the scientists, including those from La Jolla Institute (LJI) in the US, cautioned that it is too soon to say whether such pre-existing immune cell memory affects COVID-19 clinical outcomes. "We have now proven that, in some people, pre-existing T cell memory against common cold coronaviruses can cross-recognise SARS-CoV-2, down to the exact molecular structures," said Daniela Weiskopf, a co-author of the study from LJI. "This could help explain why some people show milder symptoms of disease while others get severely sick," Weiskopf said. Alessandro Sette, another co-author of the study from LJI, noted that the reactivity of the immune system may translate to different degrees of protection. "Having a strong T cell response, or a better T cell response may give you the opportunity to mount a much quicker and stronger response," Sette said. An earlier study by Sette and his team had shown that 40 to 60 per cent of people who were never exposed to the novel coronavirus SARS-CoV-2 had T cells that reacted to the virus. According to the study, the immune systems in these individuals recognised fragments of the virus it had never seen before -- a finding which was also reported among people in the Netherlands, Germany, Singapore, and the UK. In the current research, the scientists assessed samples collected from study participants who had never been exposed to SARS-CoV-2. They defined the exact parts of the virus that are responsible for the cross-reactive T cell response. Their analysis showed that unexposed individuals can produce a range of memory T cells that are equally reactive against SARS-CoV-2, and four types of common cold coronaviruses. Based on the finding, the scientists said fighting off a common cold coronavirus could teach the T cell compartment to recognise some parts of SARS-CoV-2 as well. They believe this process provides evidence for the hypothesis that common cold viruses can, in fact, induce cross-reactive T cell memory against SARS-CoV-2. "We knew there was pre-existing reactivity, and this study provides very strong direct molecular evidence that memory T cells can ''see'' sequences that are very similar between common cold coronaviruses and SARS-CoV-2," Sette said. The scientists found that while some cross-reactive T cells targeted the SARS-CoV-2''s spike protein -- the region of the virus that recognises and binds to human cells -- pre-existing immune memory was also directed to other SARS-CoV-2 proteins. Sette noted that the finding is relevant since most vaccine candidates target the spike protein. The findings, according to the researchers, suggest the hypothesis that inclusion of additional SARS-CoV-2 targets might enhance the potential to take advantage of this cross reactivity, and could further enhance vaccine potency. Copyright © Jammu Links News, Source: Jammu Links News

Read More........→August 06, 2020