San Francisco, June 23 (Xinhua/UNB) -- Antibiotic-resistant bacteria could be transmitted to humans through consumption of plant foods, which may pose health risks for the general public, according to a study unveiled on Saturday.
Researchers at the University of Southern California (USC) discovered how plant foods serve as vehicles for spreading antibiotic resistance to the gut microbiome, said a study presented to ASM Microbe 2019, an annual meeting of the American Society for Microbiology (ASM) being held here from June 20 to 24.
During a mouse experiment, the scientists observed antibiotic bacteria or "superbugs" successfully hid in the intestines of the mice fed with lettuce contaminated with the antibiotic-resistant bacteria of E. coli.
"We found differences in the ability of bacteria to silently colonize the gut after ingestion, depending on a variety of host and bacterial factors," said Marlene Maeusli, a USC researcher and lead author on the study.
Unlike the outbreaks of diarrheal illnesses caused immediately after humans eat contaminated vegetables, the antibiotic-resistant bacteria can hide in the human intestines for months or even years before they cause an illness such as a urinary infection, said the study.
"Our findings highlight the importance of tackling foodborne antibiotic-resistance from a complete food chain perspective that includes plant-foods in addition to meat," Maeusli said.
About 2 million cases of antibiotic-resistant infections occur every year in the United States and 20 percent of them are linked to agriculture, according to the estimates of the U.S. Centers for Disease Control and Prevention.
Portland, Jun 22 (AP/UNB) — So many gray whales are dying off the U.S. West Coast that scientists and volunteers dealing with the putrid carcasses have an urgent request for coastal residents: Lend us your private beaches so these ocean giants can rot in peace.
The number of dead whales washing ashore in Washington state alone — 29 as of this week — means almost every isolated public beach has been used. Authorities are now scrambling to find remote stretches of sand that are privately owned, with proprietors who don't mind hosting a rotting creature that's bigger than a school bus and has a stench to match its size.
"The preferred option is, at all times, that they just be allowed to decompose naturally," said John Calambokidis, a research biologist with the Olympia, Washington-based Cascadia Research. "But it gets harder and harder to find locations where they can rot without creating a problem. This is a new wrinkle."
At least 81 gray whale corpses have washed ashore in California, Oregon, Washington and Alaska since Jan. 1. If tallies from Mexico and Canada are added, the number of stranded gray whales reaches about 160 and counting, said Michael Milstein, spokesman for NOAA Fisheries.
U.S. scientists last month declared the die-off an "unusual mortality event," a designation that triggered additional resources to respond to the deaths and launch an investigation.
The first private-beach owners to respond, a Washington state couple, received their carcass earlier this month. Volunteers with the so-called "stranding network" — a coalition of nonprofits, research institutions and government agencies — attached a rope to the dead whale's tail and used a motorboat to tow it 3 miles (4.8 kilometers) along the coast to the couple's beach, where they anchored it to tree stumps.
Mario Rivera and his veterinarian wife, Stefanie Worwag, asked their neighbor's permission first and are using copious amounts of lime to speed decomposition and reduce the stench. They visit the carcass daily and consider it a scientific opportunity.
"It's decomposing nicely. There've been a couple of days this week when I was out there mowing and I was like, 'Oooph,'" Rivera said of smell from the 40-foot (12-meter) adult male whale sitting 150 yards (137 meters) from his house.
"But it's only temporary. It's only going to be smelling for about a month — and after that, the smell's gone."
Since the Port Townsend, Washington, couple welcomed the carcass, 15 more private individuals have signed on to do the same, mostly in remote areas around the Salish Sea in far northwest Washington state, Milstein said.
The number of dead whales found in Washington state this year has already surpassed the tally for 2000, when the last significant die-off of gray whales occurred on the West Coast. In Oregon, five dead gray whales have been documented as of this week, more than in all of last year. California has seen 37, and 10 have come ashore in Alaska.
Experts estimate the washed-up whales represent just 10 percent of the total number of the dead, with the rest sinking into the sea unnoticed by humans.
In past years, the majority of stranded whales were left to rot in place after necropsies were done. A few were buried, hauled to a landfill or sunk at sea. Towing them back out to sea isn't the preferred method because the bodies could wash up again or could cause problems if they float into shipping channels and collide with boats.
Officials have learned how not to dispose of whale carcasses from experience, including a 1970 attempt to blow up a dead sperm whale with dynamite in Oregon. The blast sent chunks of burning, rotting blubber raining down on spectators, and several cars in a nearby parking lot were crushed by blobs of putrid flesh.
Now, it's about "getting people to step up and say, 'Yeah, we can take these animals and have them on our beach,'" said Betsy Carlson, the citizen science coordinator for the Port Townsend Marine Science Center.
"There's such sadness in them just washing up on the shores and seeing these big, majestic animals there."
It's a disappointing twist in what is otherwise considered a success story for species recovery.
The eastern North Pacific gray whales were removed from the endangered species list in 1994, after rebounding from the whaling era. The population has grown significantly in the past decade and is now estimated at 27,000 — the highest since surveys began in 1967.
But that has raised questions about whether their population has reached the limit of what the environment can sustain, causing a rash of starvation. Another theory cites the loss of Arctic sea ice due to global warming.
The whales spend their summers in the Arctic feeding on tiny shrimp-like, bottom-dwelling creatures called amphipods before migrating 10,000 miles (16,090 kilometers) to winter off Mexico, where the females give birth. Though they eat all along their route, they are typically thinning by the time they return north along the West Coast each spring.
Although scientists are far from an answer about the die-off, whale expert Calambokidis wonders if fluctuations in the food supply because of global warming are having an outsized impact on the whales because their population has increased.
"It isn't like there are twice as many gray whales this year as there were last year," he said. "The increases (in numbers) are small, so why would you expect this huge jump in deaths? There has to be some other variable."
The whales that have washed up this year are emaciated, and scientists have also noted that whales migrating north are showing up in places they wouldn't normally venture, such as the Ports of Los Angeles and Long Beach, California, or San Francisco Bay. That leads researchers to wonder if the gigantic mammals are veering off course in a desperate bid to find food far south of where they usually fatten up in the late summer months.
The dead whale Rivera and Worwag have on their beach had a stomach full of eel grass, far from its normal diet. A necropsy showed the adult male starved to death.
"This whale was desperation feeding," said Rivera. "It's like a starving human eating grass to stay alive. It just can't."
Washington, June 21 (Xinhua/UNB) -- An international team led by Chinese scientists explained why deer are less likely to develop cancer, how reindeer adapt to the harsh environments, and how they produce more Vitamin D. The answers could have far-reaching medical implications.
A trio of reports published on Thursday in the journal Science mapped out the genomes of 44 ruminant species, a group of multi-stomached mammals including deer, cow and goat.
Researchers from more than 20 organizations including Northwestern Polytechnical University, Northwest A&F University and Chinese Academy of Sciences published their initial findings with the Ruminant Genome Project, producing an evolutionary tree of the ruminant group.
They also found significant declines in ruminant populations nearly 100,000 years ago when humans migrated out of Africa, revealing early humans' impact on ruminant species.
In the second paper, the researchers used the genome map and found the growth of antlers -- as much as 2.5 centimeters a day -- was only made possible as those headgear-bearing ruminant animals utilized cancer-linked molecular pathways and highly expressed tumor suppressing genes. The findings lend a clue to a new protective mechanism against cancer.
Reindeer thriving in harsh Arctic conditions like extreme cold and prolonged periods of light and dark have been scrutinized in the third paper. They turned out to acquire a gene mutation that deprives the reindeer of the circadian clocks so that they can live without sleeping disorder through long nights and long days.
It may inspire scientists to design a drug to cure sleeping diseases or help astronauts adjust their biological clocks during space travel.
Also, the researchers revealed how supercharged Vitamin D-using genes in reindeer were evolved to help them absorb more calcium, which made the antler rapid growth possible. This can be a potential molecular mechanism used to treat brittle-bone disease, according to the study.
The findings provide vital insights into genetic adaptations that are responsible for ruminant animals' biological success, said Stanford researcher Yang Yunzhi, who wrote a perspective article in the journal to review the three papers.
"Understanding the evolution of ruminant animals can improve our research in regenerative medicine, tumor biology, sleeping disorder and osteoporosis, and it may also help us breed new livestock in the future," the paper's corresponding author Wang Wen, researcher of Kunming Institute of Zoology under Chinese Academy of Sciences, told Xinhua.
Alaska, June 20 (AP/UNB) — It's not America's Top 40, but it's a cutting edge song.
Federal marine biologists for the first time have recorded singing by one of the rarest whales on the planet, the North Pacific right whale.
National Oceanic and Atmospheric Administration researchers used moored acoustic recorders to capture repeated patterns of calls made by male North Pacific right whales.
It's the first time right whale songs in any population have been documented, said NOAA Fisheries marine biologist Jessica Crance on Wednesday from Seattle. She spoke to southern right whale and North Atlantic right whale experts to confirm that singing had not previously been documented.
Researchers detected four distinct songs over eight years at five locations in the Bering Sea off Alaska's southwest coast, Crance said.
Only about 30 of the animals remain. Whalers nearly wiped out the slow-moving whales, which remain buoyant after they are killed.
Humpback, bowhead and other whales are known for their songs. During a field survey in 2010, NOAA Fisheries researchers first noted weird sound patterns they could not identify.
"We thought it might be a right whale, but we didn't get visual confirmation," Crance said.
The researchers reviewed long-term data from acoustic recorders and noted repeating sound patterns. Seven years of frustration followed, Crance said, as they could never positively confirm that the sounds were coming from the scarce right whales.
The breakthrough came in 2017. Crance and her team heard one of the whale songs in real time from the acoustic recorders on buoys. Researchers can receive sound from up to four buoys at once and point them toward the source. That allowed them to triangulate the position of the whale making the song. From previous surveys and genetic studies, they identified it as a male right whale.
"It was great to finally get the confirmation when we were out at sea that yes, it is a right whale, and it's a male that's singing," Crance said.
Right whales make a variety of sounds. A predominant call sounds like a gunshot. They also make upcalls, downcalls, moans, screams and warbles.
To be a song, the sounds have to contain rhythmically patterned series of units produced in a consistent manner to form clearly recognizable patterns, Crance wrote in a paper for the Journal of the Acoustical Society of America.
"It's a series of sounds that are reproduced in a stereotyped, regular manner that are repeated over and over," she said.
Structurally, in timing and number of sounds, right whale songs resemble those of the Atlantic walrus, she said. Both are filled with impulses, with walruses substituting knocking sounds for gunshot sounds.
The discovery almost raises more questions than answers, Crance said.
"Is it the only population to sing or does it occur in other species and populations?" she asked.
"It could be that there are so few of them left, they feel the need to call more frequently or sing," Crance said. "This is entirely speculation, but perhaps they're copying humpbacks, a little bit. Our right whales are frequently seen associating with humpbacks."
The remote Bering Sea makes studying right whales a challenge. Their range remains unknown. Some years NOAA Fisheries researchers see no right whales on their summer voyages. They spotted what they believe was a juvenile in 2017 but the last Bering Sea mother-calf pairing was seen in 2004, Crance said.
A singing male may be trying to attract a female, she said.
"With only 30 animals, finding a mate must be difficult," Crance said.
New York, Jun 8 (AP/UNB) — You've heard about the International Space Station for years. Want to visit?
NASA announced Friday that the orbiting outpost is now open for business to private citizens, with the first visit expected to be as early as next year.
There is a catch, though: You'll need to raise your own cash, and it won't be cheap.
A round-trip ticket likely will cost an estimated $58 million. And accommodations will run about $35,000 per night, for trips of up to 30 days long, said NASA's chief financial officer Jeff DeWit.
"But it won't come with any Hilton or Marriott points," DeWit said during a news conference at Nasdaq in New York City.
Travelers don't have to be U.S. citizens. People from other countries will also be eligible, as long as they fly on a U.S.-operated rocket.
Since the space shuttle program ended in 2011, NASA has flown astronauts to the space station aboard Russian rockets. The agency has contracted with SpaceX and Boeing to fly future crewed missions to the space station. Private citizens would have to make travel arrangements with those private companies to reach orbit.
"If a private astronaut is on station, they will have to pay us while they're there for the life support, the food, the water, things of that nature," DeWit added.
Depending on the market, the agency will allow up to two visitors per year, for now. And the private astronauts will have to meet the same medical standards, training and certification procedures as regular crew members.
The space station has welcomed tourists before by way of Russian rockets. In 2001, California businessman Dennis Tito became the first visitor by paying for a journey and several others have followed.
Friday's announcement marks the first time NASA is allowing private astronauts on board. The space agency will not be selling directly to customers. Instead it will charge private companies that ferry passengers, which can pass on the costs to visitors, NASA spokeswoman Stephanie Schierholz said in an email.
The program is part of NASA's efforts to open the station to private industries, which the agency hopes will inherit the orbiting platform someday.
Eventually, the space station will become too expensive for the government to maintain, said Bill Gerstenmaier, a NASA associate administrator. So the idea is to let the private sector start using the station now and perhaps eventually take it over, he said.
The NASA officials said some revenue from commercial activities will help the agency focus its resources on returning to the moon in 2024, a major goal of the Trump administration. The agency said this will also reduce the cost to U.S. taxpayers for this next lunar mission.