The Week - USA (2021-02-12)

Health & Science NEWS 21

Paralyzed mice walk again

Scientists in Germany have given paralyzed

mice the ability to walk again by inject-

ing a designer protein into their brain, a

breakthrough that could offer hope to the

5.4 mil lion people worldwide who suffer

from paralysis. Spinal injuries in humans,

often a result of sports or traffic accidents,

can result in permanent paralysis because

not all of the nerve fibers that carry infor-

mation between the brain and muscles are

able to regrow. Such damage was thought

to be irreparable in mammals. But in the

new study, researchers from Ruhr University

Bochum found the designer protein sparked

new growth in the paralyzed mice’s nerve

cells. The rodents, which had lost mobility

in both hind legs, began walking within two

to three weeks of receiving the treatment.

“With a relatively small intervention, we

stimulate a very large number of nerves to

regenerate,” lead researcher Dietmar Fischer

tells Reuters.com. Fischer and his team

hope to improve their treatment and try it

on larger mammals such as pigs, dogs, or

monkeys. “If it works there,” he says, “we

would have to make sure that the therapy is

safe for humans, too. But that will certainly

take many, many years.”

Antibiotics may stunt growth

Boys given antibiotics within two weeks

of being born are more likely to grow at a

slower rate, new research suggests—but the

same isn’t true of girls. Researchers at the

University of Helsinki recorded the growth

of some 12,422 children from birth until

age 6. Of these, 1,151 were treated with

antibiotics within 14 days of birth, for sus-

pected bacterial infections. The boys in this

group were more likely to have significantly

lower height and weight gain over the next

six years, compared with the children who

didn’t receive antibiotics. In girls there was

no discernible difference. The researchers

think the disparity between the sexes is

probably linked to differences in intestinal

gene expression: Antibiotics may cause

long-term changes in boys’ gut microbiome,

potentially by killing “good bacteria” that

help digest food, train our immune system,

protect us from “bad” bacteria and perform

other useful functions. They tested this

theory by implanting microbes from the

babies’ feces into young mice. Sure enough,

the male mice given microbes from babies

treated with antibiotics grew up smaller.

Lead researcher Samuli Rautava tells New

Scientist that the findings show “for the first

time that antibiotic exposure during the first

days of life has long-term effects.”

Short naps to improve the brain

A nap in the afternoon may improve your

brain function, reports The Daily Telegraph

(U.K.). Researchers in China examined the

sleeping habits and brain function of more

than 2,000 adults over 60. They found that

those who took a nap— defined as a post-

lunch doze that lasts between five minutes

and two hours— performed “significantly”

better in health checks and cognitive

assessments than those who didn’t get any

daytime shuteye. The nappers appeared to

speak more fluently and performed better

in tests on problem solving, memory recall,

and awareness of their surroundings. The

researchers didn’t determine the cause of

these enhanced responses but noted that nap-

ping regulates inflammatory chemicals linked

to sleep disorders, which in turn can cause

health problems. Sleep expert Neil Stanley,

who wasn’t involved in the research, says

napping lets you “zone out from all of the

noise so your brain can do its housekeeping.”

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On the move after receiving the brain injection

In a boost for parents eager to get their

children back in classrooms, the Centers

for Disease Control has concluded that

schools can safely reopen for in-person

education—so long as mask wearing and

social distancing are maintained. “With

proper prevention efforts [we] can keep

transmission in schools and educational

settings quite low,” lead author Margaret

Honein tells The Washington Post. “We

didn’t know that at the beginning of the

year, but the data has really accumulated.”

The CDC analyzed data from K-12 schools

in both the U.S. and abroad that reopened

for in-person instruction last fall. It found

that the rapid viral spread seen in nursing

homes and high- density workplaces such

as meatpacking plants didn’t happen in

schools. Among the research cited was a

study involving 90,000 students and staff

in North Carolina, which found that only

32 infections were acquired in school com-

pared with 773 in the wider community.

The CDC recommends that if schools do

reopen, they should mandate masks, allow

for a distance of 6 feet between people,

increase air ventilation, implement Covid

testing, and keep students in small cohorts

to limit the number who have to quaran-

tine in the case of an exposure. Indoor

sports and other close- contact activities

should be suspended: A December high

school wrestling tournament in Florida

that the CDC examined resulted in at least

79 infections and one death.

Schools safe to open—with precautions

Lining up for school in New York City

It’s no secret that cats love

catnip. Present a kitty with

a toy filled with the stuff

and the animal will rub it

all over its face, run wild

for a few minutes, and

then collapse in a state

of euphoria. But a new

study suggests our feline

friends get more than a

buzz from catnip: The plant may also pro-

tect them from mosquitoes. Catnip and

another plant, silver vine, contain iridoids,

chemicals responsible for the ecstatic

response in cats, reports The New York

Times. For the study, researchers rubbed

silver vine on the heads of house cats and

exposed them to a swarm

of mosquitos. The insects

feasted on the cats that

hadn’t been rubbed—and

snubbed those that had.

The researchers say more

research is needed to

determine whether cats

are attracted to catnip

because of its mosquito-

repelling qualities or

if it’s just a useful side

benefit. Either way, lead researcher Masao

Miyazaki, from Iwate University in Japan,

says iridoids could potentially be used as

a bug repellant for humans. To test the

idea, Miyazaki slathered his arm with sil-

ver vine iridoids and held it in a cage full

of mosquitos. The insects didn’t bite.

Blissed out and mosquito free

Catnip does more than get cats high