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Pre-embryos made in lab could spur research, ethics debates – CBC.ca

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For the first time, scientists have used human cells to make structures that mimic the earliest stages of development, which they say will pave the way for more research without running afoul of restrictions on using real embryos.

Two papers published Wednesday in the journal Nature detail how two teams of scientists independently made such structures.

They stressed that their work is only for research, not reproduction, but it likely will pose new ethical questions.

“Studying early human development is really difficult. It’s basically a black box,” said Jun Wu, a stem cell biologist at the University of Texas, Southwestern Medical Center. “We believe our model can open up this field,” he said, if “you can test your hypothesis without using human embryos.”

Wu’s team used embryonic stem cells and the second team used reprogrammed skin cells to produce balls of cells that resemble one of the earliest stages of human development. These balls, called blastocysts, form a few days after an egg has been fertilized but before the cells attach to the uterus to become an embryo.

To differentiate their models from blastocysts created through fertilization, the researchers refer to the structures as “iBlastoids” and “human blastoids.”

Larger scale research

“They shouldn’t be considered as equal to a blastocyst, although they are an excellent model for some aspects of biology,” said Jose Polo, an epigeneticist at Monash University in Australia who led the second research team.

Both groups stressed that the structures they made were not the same as naturally occurring embryos, and it’s unclear whether they could develop into viable embryos.

“The blastoids are less efficient in terms of generating structures mimicking later stage human embryos,” said Wu, whose team stopped growing the structure in a culture after four days.

Scientists previously generated similar structures of mouse cells in a lab, but this is the first time they have been made from human cells. The new models correspond to about three to 10 days after fertilization, Wu said.

Last year, researchers unveiled structures that model cells 18 to 21 days after fertilization. Research involving human embryos and blastocysts is currently ineligible for federal funding in the U.S., and several states prohibit it outright.

Some scientists now use blastocysts donated from fertility clinics for research into the causes of infertility and congenital diseases.

The new work should allow them to do such research at much larger scales, Polo said. “This capacity to work at scale will revolutionize our understanding of these early stages of human development,” said Polo.

‘There is no pregnancy’

Scientists edit embryos’ genes to study early human development The scientists stressed that their creations were not intended to be used for human reproduction.

“There is no implantation,” said Amander Clark, a stem cell biologist at the University of California, Los Angeles who co-authored the paper with Polo. “These structures are not transferred to a uterus or uterus-like structure,” she said. “There is no pregnancy.”

The distinction between blastocysts derived from fertilization and the structures created in a lab may not be so clear-cut, said Shoukhrat Mitalipov, a human embryologist at Oregon Health and Science University who was not involved in the research.

“Both groups show how closely they resemble real embryos,” he said. “If they are really as good as embryos, should they be treated as embryos?” “This brings new ethical issues,” he said. “Are they going to be covered as human embryos? Should restrictions apply?”

Scientists previously tried to turn the lab-generated mouse cell structures into embryos, but they were not successful. The optimal scenario for research is to “get as close to a real embryo as possible so you can learn from it, but not a real embryo so you don’t get into debates about the moral status of embryos,” said Alta Charo, a professor emerita of law and bioethics at University of Wisconsin who was not involved in the papers.

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.

Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.

She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.

Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.

“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.

It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.

Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.

Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.

Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.

“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.

He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

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B.C. sets up a panel on bear deaths, will review conservation officer training

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VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

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