Scientists close in on blood test for Alzheimer’s

In this July 9, 2019 photo, Dr. Jori Fleisher, neurologist, examines Thomas Doyle, 66, at the Rush University Medical Center in Chicago. (AP)
Updated 16 July 2019

Scientists close in on blood test for Alzheimer’s

  • One of the experimental blood tests measures abnormal versions of the protein that forms the plaques in the brain that are the hallmark of Alzheimer’s

LOS ANGELES: Scientists are closing in on a long-sought goal — a blood test to screen people for possible signs of Alzheimer’s disease and other forms of dementia.
On Monday at the Alzheimer’s Association International Conference, half a dozen research groups gave new results on various experimental tests, including one that seems 88% accurate at indicating Alzheimer’s risk.
Doctors are hoping for something to use during routine exams, where most dementia symptoms are evaluated, to gauge who needs more extensive testing. Current tools such as brain scans and spinal fluid tests are too expensive or impractical for regular check-ups.
“We need something quicker and dirtier. It doesn’t have to be perfect” to be useful for screening, said Maria Carrillo, the Alzheimer’s Association’s chief science officer.
Dr. Richard Hodes, director of the National Institute on Aging, called the new results “very promising” and said blood tests soon will be used to choose and monitor people for federally funded studies, though it will take a little longer to establish their value in routine medical care.
“In the past year we’ve seen a dramatic acceleration in progress” on these tests, he said. “This has happened at a pace that is far faster than any of us would have expected.”
It can’t come too soon for patients like Tom Doyle, a 66-year-old former university professor from Chicago who has had two spinal fluid tests since developing memory problems four years ago. First he was told he didn’t have Alzheimer’s, then that he did. He ultimately was diagnosed with different problems — Lewy body dementia with Parkinson’s.
“They probably could have diagnosed me years ago accurately if they had had a blood test,” said Doyle, who represents patients on the Alzheimer’s Association’s board.
About 50 million people worldwide have dementia, and Alzheimer’s is the most common form. There is no cure; current medicines just temporarily ease symptoms. Dozens of hoped-for treatments have failed. Doctors think studies may have enrolled people after too much brain damage had occurred and included too many people with problems other than Alzheimer’s.
A blood test — rather than subjective estimates of thinking skills — could get the right people into studies sooner.

One of the experimental blood tests measures abnormal versions of the protein that forms the plaques in the brain that are the hallmark of Alzheimer’s. Last year, Japanese researchers published a study of it and on Monday they gave results from validation testing on 201 people with Alzheimer’s, other types of dementia, mild impairment or no symptoms.
The blood test results closely matched those from the top tests used now — three types of brain scans and a mental assessment exam, said Dr. Akinori Nakamura of the National Center for Geriatrics and Gerontology in Obu, Japan. The test correctly identified 92% of people who had Alzheimer’s and correctly ruled out 85% who did not have it, for an overall accuracy of 88%.
Shimadzu Corp. has rights to the test and is working to commercialize it, Nakamura said.
Another experimental test looks at neurofilament light, a protein that’s a marker of nerve damage. Abdul Hye of King’s College London gave results of a study comparing blood levels of it in 2,300 people with various neurological conditions — Alzheimer’s, other dementias, Parkinson’s, depression, multiple sclerosis, Lou Gehrig’s disease — plus healthy folks for comparison.
Levels were significantly higher in eight conditions, and only 2% of healthy folks were above a threshold they set for raising concern. The test doesn’t reveal which disorder someone has, but it may help rule one out when symptoms may be psychological or due to other problems.
Later at the conference, Dr. Randall Bateman of Washington University School of Medicine in St. Louis will give new results on a blood test he helped develop that the university has patented and licensed to C2N Diagnostics, a company he co-founded. Like the Japanese test, it measures the abnormal Alzheimer protein, and the new results will show how well the test reflects what brain scans show on nearly 500 people.
“Everyone’s finding the same thing ... the results are remarkably similar across countries, across techniques,” said Bateman, whose work is supported by the US government and the Alzheimer’s Association. He estimates a screening test could be as close as three years away.
What good will that do without a cure?
An Associated Press-NORC Center for Public Affairs Research poll last year found that most Americans would want to know if they carried a gene tied to a disease even if it was incurable.
“What people want most of all is a diagnosis” if they’re having symptoms, said Jonathan Schott of University College London. “What we don’t like is not knowing what’s going on.”


Alexei Leonov, 1st human to walk in space, dies in Moscow

In this Tuesday, July 20, 2010 file photo, former Russian cosmonaut Alexei Leonov speaks to the media before a reception at the U.S. Ambassador's Spaso House residence in Moscow, Russia. (AP)
Updated 12 October 2019

Alexei Leonov, 1st human to walk in space, dies in Moscow

  • NASA on Friday offered its sympathies to Leonov’s family, saying it was saddened by his death

MOSCOW: Alexei Leonov, the legendary Soviet cosmonaut who became the first human to walk in space 54 years ago — and who nearly didn’t make it back into his space capsule — has died in Moscow at 85.
The Russian space agency Roscosmos made the announcement on its website Friday but gave no cause for his death. Leonov had health issues for several years, according to Russia media.
Showing just how much of a space pioneer Leonov was, NASA broke into its live televised coverage of a spacewalk by two Americans outside the International Space Station to report Leonov’s death.
“A tribute to Leonov as today is a spacewalk,” Mission Control in Houston said.
Leonov — described by the Russian Space Agency as Cosmonaut No. 11 — was an icon both in his country as well as in the US He was such a legend that the late science fiction writer Arthur C. Clarke named a Soviet spaceship after him in his “2010” sequel to “2001: A Space Odyssey.”
Russian President Vladimir Putin on Friday sent his condolences to Leonov’s family, calling him a “true pioneer, a strong and heroic person.”
“Infinitely committed to his vocation, he left a truly legendary mark in the history of space exploration and in the history of our country,” Putin said on the Kremlin’s website.
Leonov was born in 1934 into a large peasant family in western Siberia. Like countless Soviet peasants, his father was arrested and shipped off to Gulag prison camps under Soviet dictator Josef Stalin, but he managed to survive and reunite with his family.
The future cosmonaut had a strong artistic bent and even thought about going to art school before he enrolled in a pilot training course and, later, an aviation college. Leonov did not give up sketching even when he flew into space, and took colored pencils with him on the Apollo-Soyuz flight in 1975 to draw.
That mission was the first one between the Soviet Union and the United States and was carried out at the height of the Cold War. Apollo-Soyuz 19 was a prelude to the international cooperation seen aboard the current International Space Station.
But Leonov staked his place in space history ten years earlier, on March 18, 1965, when he exited his Voskhod 2 space capsule secured by a tether.
“I stepped into that void and I didn’t fall in,” the cosmonaut recalled years later. “I was mesmerized by the stars. They were everywhere — up above, down below, to the left, to the right. I can still hear my breath and my heartbeat in that silence.”
Spacewalking always carries a high risk but Leonov’s pioneering venture was particularly nerve-wracking, according to details of the exploit that only became public decades later.
His spacesuit had inflated so much in the vacuum of space that he could not get back into the spacecraft. He had to open a valve to vent oxygen from his suit to be able to fit through the hatch.
Leonov’s 12-minute spacewalk preceded the first US spacewalk, by Ed White, by less than three months.
Leonov might have become the Soviet Union’s first moonwalker, in fact, had his country’s lunar-landing effort not been canceled in the wake of Apollo 11’s triumphant moon landing by Neil Armstrong and Buzz Aldrin on July 20, 1969.
On his second trip into space ten years later, Leonov commanded the Soviet half of Apollo-Soyuz 19.
The cosmonaut was well known for his humor. Once the US Apollo and Soviet Soyuz capsules docked in orbit around Earth on July, 17, 1975, Leonov and his Russian crewmate, Valeri Kubasov, welcomed the three US astronauts — their Cold War rivals — with canned borscht disguised as Stolichnaya vodka and suggested a toast.
“When we sat at the table, they said: ‘Why, that’s not possible,’” Leonov recalled in 2005. “We insisted, saying that according to our tradition, we must drink before work. That worked, they opened it and drank (the borscht) and were caught by surprise.”
The cosmonaut turned 85 in May. Several days before that, two Russian crewmembers on the International Space Station ventured into open space on a planned spacewalk, carrying Leonov’s picture with them to pay tribute to the space legend. They said “Happy Birthday!” to Leonov before opening the hatch and venturing out.
Leonov’s modern-day successor, Oleg Kononenko, who was one of the two Russians on that spacewalk, told Rossiya-24 television on Friday that Leonov had tuned in to hear their congratulations from space.
“We were going to stop by Alexei Arkhipovich (Leonov) after our return and give him our space souvenirs, but you see it wasn’t meant to be,” Kononenko said.
When his crew returned to earth at the end of June, Leonov was already unwell.
Kononenko spoke fondly of the Soviet space pioneer, saying he was a frequent guest at send-off ceremonies for space crews in Star City and at the cosmodrome in Baikonur, Kazakhstan.
“We had this tradition that he would give cosmonauts pep talks before they board the spacecraft,” Kononenko said. “We all looked forward to that, always thought about it and always wanted Leonov to be the one to send us off into space.”
Messages of condolences poured from around the globe.
NASA on Friday offered its sympathies to Leonov’s family, saying it was saddened by his death.
“His venture into the vacuum of space began the history of extra-vehicular activity that makes today’s Space Station maintenance possible,” NASA said on Twitter.
“One of the finest people I have ever known,” former Canadian astronaut Chris Hadfield tweeted on Friday. “Alexei Arkhipovich Leonov, artist, leader, spacewalker and friend, I salute you.”
Russian space fans were bringing flowers to his monument Friday on the memorial alley in honor of Russia’s cosmonauts in Moscow.
Leonov, who will be buried on Tuesday at a military memorial cemetery outside Moscow, is survived by his wife, a daughter and two grandchildren.