Mystery behind large size of human brain unravelled

Agencies
May 25, 2018

Paris, May 25: The human brain is disproportionately large. And while abundant grey matter confers certain intellectual advantages, sustaining a big brain is costly — consuming a fifth of energy in the human body.

It is an oddity that has long flummoxed scientists: while most organisms thrive with small brains, or none at all, the human species opted to sacrifice a degree of body growth for more cerebral capacity.

The human brain, scientists say, expanded mainly in response to environmental stresses that forced our species to come up with innovative solutions for food and shelter, and pass the lessons on to our offspring.

The finding challenges a popular theory that the thinking organ grew as social interactions between humans became more complex, a research duo wrote in the Nature.

Ecological problem-solving

“The large human brain is more likely to stem from ecological problem-solving and cumulative culture than it is from social manoeuvering,” said paper co-author Mauricio Gonzalez-Forero of the University of St Andrews in Scotland.

From our ape-like Australopithecus ancestors to modern Homo sapiens, the human brain has tripled in size. But feeding such a big brain has been suggested to come at the cost of slow body growth in childhood — leaving our young dependent and vulnerable for longer than other animals.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
May 18,2020

China, where the novel coronavirus originated, has reported 111 cases since beginning of May, which shows the infection rate has dipped, and 3 deaths since April 27, according to the WHO. A Shanghai-based Noida doctor says China is close to winning the battle against COVID-19, and the combination of zinc, hydroxychloroquine (HCQ) and antibiotic azithromycin has been able to save the lives of coronavirus patients.

Speaking to media persons, Dr Sanjeev Choubey, Medical Director Internal Medicine at St. Michael Hospital said this combination has been adopted as a line of treatment for patients infected with coronavirus, and as a result patients are recovering, decreasing their need for intensive care.

What is the line of treatment for COVID-19 patients, which also include asymptomatic patients?

The combination of zinc, hydroxychloroquine and antibiotic azithromycin has produced positive results, and it helped in the recovery of many COVID-19 patients. The combination -- Ascorbic Acid, B-complex, Zinc, Selenium, L-carnitine, Vitamin B-12 and Glutathione normal saline should be administered on patients twice a week for at least 6 weeks. This is COVID-19 treatment protocol for prophylaxis, and it implies both asymptomatic and symptomatic along with other medicine support.

Based on your experience on COVID-19 in China, after how many tests, is it safe to call a person coronavirus free?

The coronavirus should be performed at least 9 times, before terming a patient COVID-19 free. It is a standard in China. This procedure has worked in China and it will also work in India. Minimum five tests should be mandatory through RT-PCR.

Does coronavirus majorly attack the respiratory system or it could lead to organ failure too?

Line of treatment should not be just looking at the respiratory system, as the problem lies somewhere else. COVID-19 attacks many vital organs in the body. In China, a coronavirus patient died from a stroke. In the autopsy it was found that the innermost layer in the arteries was swollen. It was concluded that coronavirus had inflamed the layer of the arteries leading to clotting, which was a factor in generating a heart attack. Therefore, COVID-19 is not just a respiratory problem.

Amid the coronavirus pandemic, should autopsy be made mandatory in the case of unpredictable death or where reasons for death are not unknown?

Patients below 50 years, who die suddenly and the reasons are not known, then it should be mandatory to conduct the autopsy. After death, coronavirus is active in the body for five days, and it fades away on day 6. Therefore, if an autopsy is done then it will help in understanding this disease. In China, we have seen young COVID-19 patients, aged 22 and 28, succumbed to strokes.

Since the beginning of May, India has recorded more than 2,000 cases everyday in the first week, then it jumped past 3,000 mark in the second week. Finally, the tally is 4,987 on May 17. At 90,927 cases, has India progressed into community transmission or Stage3?

Yes, India has moved into Stage 3. The data suggests that 3,000 to 4,000 active COVID-19 cases, who are asymptomatic, are moving around and spreading the infection. The research has indicated that COVID-19 from an infected person spreads in 30 minutes to non-infected persons. The relaxation on the lockdown will certainly contribute to a high infection rate.

Do you think India has reached its peak in COVID-19 cases, or the sharp rise will continue till July end?

It seems India has already reached its peak and cases will begin to come down from June end or beginning of July first week. If social distancing norms are followed then certainly things can improve, but if not followed then it may get worse. High population density is a major contributor for the increase in cases. The government should continue to focus on finding hotspots, and urge people to follow the rules, eventually it is for people’s own benefit.

Has China won the battle against COVID-19?

It seems China has won the battle by not opening up Wuhan. The Chinese are following a COVID-19 patient’s engagement program, where the authorities continuously interact with people infected with the disease. The Government of India should reward people who follow the guidelines; it will help in setting up a positive trend in the society.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
July 3,2020

Apart from the many benefits of doing exercise, new research has now found that exercise can slow down or prevent the development of macular degeneration and may benefit other common causes of vision loss, such as glaucoma and diabetic retinopathy.

The new study from the University of Virginia School of Medicine found that exercise reduced the harmful overgrowth of blood vessels in the eyes of lab mice by up to 45 per cent. This tangle of blood vessels is a key contributor to macular degeneration and several other eye diseases.

The study represents the first experimental evidence showing that exercise can reduce the severity of macular degeneration, a leading cause of vision loss, the scientists report. Ten million Americans are estimated to have the condition.

"There has long been a question about whether maintaining a healthy lifestyle can delay or prevent the development of macular degeneration. The way that question has historically been answered has been by taking surveys of people, asking them what they are eating and how much exercise they are performing," said researcher Bradley Gelfand, PhD, of UVA's Center for Advanced Vision Science.

"That is basically the most sophisticated study that has been done. The problem with that is that people are notoriously bad self-reporters ... and that can lead to conclusions that may or not be true. This [study] offers hard evidence from the lab for the very first time," Gelfand added.

Enticingly, the research found that the bar for receiving the benefits from exercise was relatively low - more exercise didn't mean more benefit.

"Mice are kind of like people in that they will do a spectrum of exercise. As long as they had a wheel and ran on it, there was a benefit. The benefit that they obtained is saturated at low levels of exercise," Gelfand said.

An initial test comparing mice that voluntarily exercised versus those that did not found that exercise reduced the blood vessel overgrowth by 45%. A second test, to confirm the findings, found a reduction of 32 per cent.

The scientists aren't certain exactly how exercise is preventing the blood vessel overgrowth. There could be a variety of factors at play, they say, including increased blood flow to the eyes.

Gelfand, of UVA's Department of Ophthalmology and Department of Biomedical Engineering, noted that the onset of vision loss is often associated with a decrease in exercise.

"It is fairly well known that as people's eyes and vision deteriorate, their tendency to engage in physical activity also goes down. It can be a challenging thing to study with older people. ... How much of that is one causing the other?" he said.
The researchers already have submitted grant proposals in hopes of obtaining funding to pursue their findings further.

"The next step is to look at how and why this happens, and to see if we can develop a pill or method that will give you the benefits of exercise without having to exercise," Gelfand said.

He explained, "We're talking about a fairly elderly population [of people with macular degeneration], many of whom may not be capable of conducting the type of exercise regimen that may be required to see some kind of benefit." (He urged people to consult their doctors before beginning any aggressive exercise program.)
Gelfand, a self-described couch potato, disclosed a secret motivation for the research: "One reason I wanted to do this study was sort of selfish. I was hoping to find some reason not to exercise," he joked. "It turned out exercise really is good for you."

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
July 5,2020

The deadly coronavirus that entered India while there was still nip in the air has beaten rising mercury, humid conditions, unique Indian genome and has entered monsoon season with more potency as fresh cases are only breaking all records in the country.

India recorded a single-day spike of record 24,850 new coronavirus cases on Sunday, taking its total tally to 6.73 lakh corona-positive cases.

Top Indian microbiologists were hopeful in March that after the 21-day lockdown, as summer approaches, the rise in temperature would play an important role in preventing the drastic spread of COVID-19 virus in India.

Several virologists hinted that by June this year, the impact of COVID-19 would be less than what it appeared in March-April.

The claims have fallen flat as the virus is mutating fast, becoming more potent than ever.

According to experts, the novel coronavirus is a new virus whose seasonality and response to hot humid weather was never fully understood.

"The theory was based on the fact that high temperatures can kill the virus as in sterilisation techniques used in healthcare. But these are controlled environment conditions. There are many other factors besides temperature, humidity which influence the transmission rate among humans," Dr Anu Gupta, Head, Microbiologist and Infection Control, Fortis Escorts Heart Institute, told IANS.

There is no built-up immunity to COVID-19 in humans.

"Also, asymptomatic people might be passing it to many others unknowingly. New viruses tend not to follow the seasonal trend in their first year," Gupta emphasized.

Globally, as several countries are now experiencing hot weather, the World Health Organization (WHO) reported a record hike in the number of coronavirus cases, with the total rising by 2,12,326 in 24 hours in the highest single-day increase since COVID-19 broke out.

So far over 11 million people worldwide have tested positive for the disease which has led to over 5,25,000 deaths, according to data from Johns Hopkins University. The US remained the worst-hit country with over 28 lakh cases, followed by Brazil with 15.8 lakh.

According to Sandeep Nayar, Senior Consultant and HOD, Respiratory Medicine, Allergy & Sleep Disorders, BLK Super Speciality Hospital in New Delhi, whether temperature plays a role in COVID-19 infection is highly debated.

One school of thought said in the tropical regions of South Asia, the virus might not thrive longer.

"On the other hand, another school of thought has found that novel Coronavirus can survive in a hot and humid environment and tropical climate does not make a difference to the virus. According to them, this is what distinguishes the novel coronavirus from other common viruses, which usually wane in hot weather," stressed Nayar.

Not much has been studied in the past and no definite treatment or vaccine is available to date.

"Every day, new properties and manifestation of the disease come up. As of now, the only way to prevent this monster is by taking appropriate precautions. Hand hygiene, social distancing, cough etiquette and face masks definitely reduce spread of COVID-19 infection," Nayar told IANS.

Not just top Indian health experts, even Indian-American scientists had this theory in mind that sunshine and summer may ebb the spread of the coronavirus.

Ravi Godse, Director of Discharge Planning, UPMC Shadyside Pennsylvania in the US told IANS in April: "In the summer, the humidity can go up as well, meaning more water drops in the air. If the air is saturated with water and somebody sneezes virus droplets into such air, it is likely that the droplets will fall to the ground quicker, making them less infectious. So the short answer is yes, summer/sunshine could be bettera.

According to Dr Puneet Khanna, Head of Respiratory Medicine and Pulmonology, Manipal Hospital, Delhi, COVID-19 death rates are not too different in tropical countries but since the disease affected them late it was yet to show its peak in these areas.

"The virus can survive well in hot and humid countries and this is proven now," he stressed.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.