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Salvadorans, Washington’s Builders, Face Expulsion Under Trump

NY Times - Fri, 2019-09-13 08:45
Tens of thousands of workers in and around the capital were here legally because of adversity in their homeland. Now they are fighting to stay.

Analysis: There's only one issue in the Democratic primary

CNN - Fri, 2019-09-13 08:44
A lack of agreement and a crush of urgency make health care coverage the most important issue in the Democratic primary.

Some Democrats are angry that abortion, women’s rights were ignored at debate

Washington Post - Fri, 2019-09-13 08:43
Several candidates weighed in on Twitter to lament the lack of attention to those issues at Thursday night’s event.

Speaker of UK House of Commons vows to stop Johnson 'robbing a bank' with no-deal Brexit

CNN - Fri, 2019-09-13 08:34
John Bercow, the outgoing Speaker of the UK House of Commons, has warned Prime Minister Boris Johnson against ignoring the law and implementing a no-deal Brexit on October 31, a move that he compared to "robbing a bank."

Stunning train designed to feel like a living room

CNN - Fri, 2019-09-13 08:30
Japan's love affair with trains continues to push the design envelope.

Analysis: Biden has his best debate night. That may be enough

CNN - Fri, 2019-09-13 08:29
Joe Biden was as good at Thursday night's debate as he's been in the entire campaign and perhaps close to as good as he could be.

Castro insists he wasn’t making insinuations about Biden’s age but notes ‘he’s been around a long time’

Washington Post - Fri, 2019-09-13 08:28
During a morning television interview, the Democratic White House hopeful said he had no regrets about an exchange in which he asked Biden, “Are you forgetting what you said two minutes ago?”

Help! My Hotel Doesn’t Exist

NY Times - Fri, 2019-09-13 08:24
In a new Travel column, Sarah Firshein aims to help travelers resolve their thorniest and most upsetting travel disasters. This week, she investigates a nonexistent hotel, booked on Expedia.

For most of the night, Biden weathers a volley of attacks

Washington Post - Fri, 2019-09-13 08:20
The former vice president goes on the offensive against Warren and Sanders on health care and counters attacks from others on the stage. Lower-down candidates also shine.

The Technology 202: Venture capitalists aren't laughing about Andrew Yang's 'freedom dividend' proposal

Washington Post - Fri, 2019-09-13 08:15
They applauded his idea to give $1,000 a month to 10 families.

Mugabe to get hero's burial

CNN - Fri, 2019-09-13 08:14
Former Zimbabwean President Robert Mugabe will be buried in the country's National Heroes Acre monument as a row over his final resting place is settled.

London Stock Exchange Rejects Takeover Bid From Hong Kong

NY Times - Fri, 2019-09-13 08:14
London officials, citing “fundamental flaws” in the unsolicited $37 billion offer from the Hong Kong Stock Exchange, said they saw “no merit in further engagement.”

Why acute kidney injury strikes marathon runners

Futurity.org - Fri, 2019-09-13 08:07

Fluid volume and sweat sodium losses, rather than a rise in core body temperature, are the key contributors to post-race acute kidney injury, according to a new study of marathon runners.

Legend states that after the Greek army defeated the invading Persian forces near the city of Marathon in 490 BCE, the courier Pheidippides ran to Athens to report the victory and then immediately dropped dead. The story—and the distance Pheidippides covered—inspired the modern marathon, a grueling 26.2-mile contest that attracts some 1.3 million runners annually to compete in the more than 800 races held worldwide.

While Pheidippides’ demise was more likely brought about by a 300-mile run he reportedly made just prior to his “marathon,” today’s long-distance runners face a mostly short-term but still serious physical threat known as acute kidney injury, or AKI.

“We knew from a previous study that a large number of marathoners developed short-term AKI following a race, so we wanted more specifically to pin down the causes,” says senior author Chirag Parikh, director of the Division of Nephrology at the Johns Hopkins University School of Medicine. “Our findings suggest that managing fluid volume and salt losses with a personalized regimen during the time period surrounding a marathon may help reduce the number or lessen the severity of AKI incidences afterward.”

The researchers say they also found that runners with AKI following a marathon had increased levels of a blood serum protein known as copeptin. If the connection is confirmed with future studies, they say, copeptin could be valuable as a biomarker during training for predicting post-marathon susceptibility to AKI.

What is acute kidney injury?

The National Kidney Foundation describes AKI as a “sudden episode of kidney failure or kidney damage that happens within a few hours or a few days.” It causes waste products to build up in the blood, making it hard for kidneys to maintain the correct balance of fluids in the body.

Symptoms of AKI differ depending on the cause and may include: too little urine leaving the body; swelling in legs, ankles, and around the eyes; fatigue; shortness of breath; confusion; nausea; chest pain; and in severe cases, seizures or coma. The disorder is most commonly seen in hospitalized patients whose kidneys are affected by medical and surgical stress and complications.

Similarly, a marathon subjects a runner to sustained physical stress, reduced blood flow to the kidneys, and significant increases in the metabolic rate. Together, these events severely challenge the body’s ability to keep fluid volume, electrolytes, and temperature levels—along with the regulatory responses to changes in all three—in balance. The result, as seen in 82% of the runners the same researchers evaluated in a 2017 study, was AKI that averaged two days in duration.

Measuring runners during marathons

For the latest study, the goal was to better define the risk factors and mechanism for the problem by examining 23 runners, ages 22–63, who competed in the 2017 Hartford Marathon in Connecticut.

Participants were volunteers researchers recruited through local running clubs and the marathon’s registration process. Divided nearly equally between men and women, they were all experienced runners with a body mass index ranging between 18.5–24.9, and had completed at least four races longer than 20 kilometers (12.4 miles) within the previous three years.

Researchers collected urine and blood samples from the participants at three time points: 24 hours prior to the marathon, within 30 minutes of completing the race, and 24 hours after. The researchers evaluated the samples for sodium levels; key biomolecules such as creatine phosphokinase, hemoglobin, urine protein, and copeptin; and biomarkers associated with kidney injury such as interleukin-18 and kidney injury molecule-1.

Researchers placed sweat collection patches on the runners prior to the marathon and recovered them at the 5-mile mark (because they became too saturated further in the race). They measured blood pressure, heart rate, and weight at all three time points, while runners wore a bioharness during the marathon to continually record body temperature.

Twelve of the 23 runners (55%) developed AKI after the race, while 17 (74%) tested positive for markers indicating some injury to the renal tubules, the tiny portals in the kidneys where blood is filtered.

Lost fluid and salt

In the runners with post-race AKI, the researchers observed distinct sodium and fluid volume losses. The median salt loss was 2.3 grams, with some losing as much as 7 grams.

Fluid volume loss via sweat had a midpoint level of 2.5 liters (5.2 pints), up to a maximum of 6.8 liters (14.4 pints). For comparison, a 155-pound (70-kilogram) body contains about 42 liters (85 pints) of fluid.

Core body temperature, while significantly elevated throughout a marathon, was basically the same for all runners and therefore, was not considered a causal factor for AKI. However, the researchers say that the combination of high-body temperature along with fluid and salt losses may add to the development of kidney injury.

“Putting the sodium and fluid volume loss numbers into perspective, the median salt loss for the AKI runners was about 1 1/4 teaspoons, or the entire daily amount recommended by the American Heart Association,” Parikh says. “Their median fluid volume loss was equivalent to sweating out slightly more than a 2-liter soda bottle. Beyond that, we had evidence that runners weren’t adequately keeping up with those depletions.”

In turn, Parikh says, that failure to balance the sodium and fluid losses during a marathon may account for the new study’s other relevant finding: the higher levels of copeptin seen in runners with post-race AKI.

Copeptin is a precursor to the release of vasopressin, a hormone secreted by the pituitary gland in response to reduced blood volume. It tells our kidneys and blood vessels to hold on to water, preventing a sudden drop in blood pressure and physical collapse.

“In the runners who developed AKI, we found copeptin levels as much as 20 times higher than those who did not,” Parikh says. “This is biological evidence that the AKI sufferers were severely volume down.”

Because vasopressin reduces blood flow to the kidneys, and decreases renal filtration and urine output, he adds, it also may induce inflammation and injury to the kidney tissues if secreted for an extended period of time. This may explain why a large number of marathon runners get AKI while those competing at shorter distances do not.

Parikh says future studies, using larger samples, will need to evaluate whether optimizing fluid and salt volumes in marathon runners lowers rates or reduces the severity of post-race AKI. Additionally, he says, the researchers would like to follow runners who participate in multiple marathons to look for any cumulative kidney damage.

“The long-term goal will be to document an individual runner’s metabolic and sweat profile to develop a fluid and salt replacement regimen just for him or her,” he says. “Then, runners could consume this personalized drink during the race to better maintain fluid and salt balance.”

The team’s findings appear in the Clinical Journal of the American Society of Nephrology.

Additional contributors to the work are from Johns Hopkins University, Yale University, Quinnipiac University, and the University of Colorado. Support for the study came from the Quinnipiac University Faculty Scholarship Grant, the National Institute of Diabetes and Digestive and Kidney Diseases, the O’Brien Kidney Center, the National Institutes of Health and the American Heart Association.

Source: Johns Hopkins University

The post Why acute kidney injury strikes marathon runners appeared first on Futurity.

Boris Johnson Drags the Queen Into the Brexit Quagmire

NY Times - Fri, 2019-09-13 08:05
By having the crown suspend Parliament on a potentially misleading justification, the British prime minister threatened long-settled relations with the monarchy.

Trump speaks in Baltimore for the first time since calling it a 'rodent infested mess'

CNN - Fri, 2019-09-13 08:05
President Donald Trump addressed the House Republican Conference Member Retreat dinner in Baltimore Thursday evening -- his first time visiting the city since he called it a "rat and rodent infested mess."

Looking for California in the Democratic Debate?

NY Times - Fri, 2019-09-13 08:05
Friday: What Californians need to know about the three-hour marathon. Also: A Conception fire update; and Japanese curry.
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