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Bear mauls 10-year-old in grandparents’ Connecticut backyard
Officers from the state police and DEEP’s environmental conservation force responded and shot the bear, authorities said.
The boy’s grandfather described the harrowing attack to the Republican-American of Waterbury. James Butler said his grandson was playing near a trampoline when the bear emerged from thick woods behind the house.
“I heard him yell ‘bear’ and when I looked up, I saw his leg in the bear’s mouth and the bear trying to drag him across the lawn,” Butler said.
Butler, who uses a wheelchair, wheeled his chair toward the bear and threw a metal bar at its head, he told the newspaper.
The bear released the boy but then grabbed the child a second time and used its claws to try to roll the boy onto his back, the grandfather said.
A neighbor alerted by the boy’s screams raced over and scared the bear off by brandishing a pipe and yelling, Butler said.
Once Butler and his grandson were safely inside the house, the bear returned, walking up a wheelchair ramp and peering at them through screen door, Butler said.
“We thought he was coming through the screen,” Butler said. “No doubt he was a big threat.”
The bear was fatally shot by police a short time later.
Butler, and his wife, Christina Anderson, who was inside the house when the bear attacked, said the boy suffered a puncture wound to one thigh, bite marks on a foot and ankle and claw marks on his back.
State biologist Jenny Dixon said the risk of negative bear-human interactions is increasing as Connecticut’s expanding bear population becomes acclimated to humans and develops a taste for their food.
Did Gonorrhea Give Us Grandparents?
Summary: Researchers have identified a set of genetic mutations that protect against cognitive decline in older adults. A new study suggests the selective pressure from infectious pathogens like gonorrhea may have promoted the emergence of this genetic variance in Homo sapiens.
Source: UCSD
Researchers at University of California San Diego School of Medicine previously found a set of human gene mutations that protect older adults against cognitive decline and dementia.
In a new study, published July 9, 2022 in Molecular Biology and Evolution, they focus on one of these mutated genes and attempt to trace its evolution — when and why it appeared in the human genome.
The findings suggest selective pressure from infectious pathogens like gonorrhea may have promoted the emergence of this gene variant in Homo sapiens, and inadvertently supported the existence of grandparents in human society.
The biology of most animal species is optimized for reproduction, often at the expense of future health and longer lifespans. In fact, humans are one of the only species known to live well past menopause.
According to the “grandmother hypothesis,” this is because older women provide important support in raising human infants and children, who require more care than the young of other species. Scientists are now trying to understand what features of human biology make this longer-term health possible.
When researchers previously compared human and chimpanzee genomes, they found that humans have a unique version of the gene for CD33, a receptor expressed in immune cells. The standard CD33 receptor binds to a type of sugar called sialic acid that all human cells are coated with. When the immune cell senses the sialic acid via CD33, it recognizes the other cell as part of the body and does not attack it, preventing an autoimmune response.
The CD33 receptor is also expressed in brain immune cells called microglia, where it helps control neuroinflammation. However, microglia also have an important role in clearing away damaged brain cells and amyloid plaques associated with Alzheimer’s disease. By binding to the sialic acids on these cells and plaques, regular CD33 receptors actually suppress this important microglial function and increase the risk of dementia.
This is where the new gene variant comes in. Somewhere along the evolutionary line, humans picked up an additional mutated form of CD33 that is missing the sugar-binding site. The mutated receptor no longer reacts to sialic acids on damaged cells and plaques, allowing the microglia to break them down. Indeed, higher levels of this CD33 variant were independently found to be protective against late-onset Alzheimer’s.
In trying to understand when this gene variant first emerged, co-senior author Ajit Varki, MD, Distinguished Professor of Medicine and Cellular and Molecular Medicine at UC San Diego School of Medicine, and colleagues found evidence of strong positive selection, suggesting something was driving the gene to evolve more rapidly than expected.
They also discovered that this particular version of CD33 was not present in the genomes of Neanderthals or Denisovans, our closest evolutionary relatives.
“For most genes that are different in humans and chimps, Neanderthals usually have the same version as the humans, so this was really surprising to us,” said Varki. “These findings suggest the wisdom and care of healthy grandparents may have been an important evolutionary advantage that we had over other ancient hominin species.”
Varki led the study with Pascal Gagneux, PhD, professor of pathology at UC San Diego School of Medicine and professor in the Department of Anthropology. The authors said the study provides new evidence supporting the grandmother hypothesis.
Still, evolutionary theory says reproductive success is the main driver of genetic selection, not post-reproductive cognitive health. So what was pushing the prevalence of this mutated form of CD33 in humans?
One possibility, suggest the authors, is that highly infectious diseases like gonorrhea, which can be detrimental to reproductive health, might have impacted human evolution. Gonorrhea bacteria coat themselves in the same sugars that CD33 receptors bind to. Like a wolf in sheep’s clothing, the bacteria are able to trick human immune cells to not identify them as outside invaders.
The researchers suggest that the mutated version of CD33 without a sugar-binding site emerged as a human adaptation against such “molecular mimicry” by gonorrhea and other pathogens. Indeed, they confirmed that one of the human-specific mutations was able to completely abolish the interaction between the bacteria and CD33, which would allow immune cells to attack the bacteria again.
Altogether, the authors believe humans initially inherited the mutated form of CD33 to protect against gonorrhea during reproductive age, and this gene variant was later co-opted by the brain for its benefits against dementia.
“It is possible that CD33 is one of many genes selected for their survival advantages against infectious pathogens early in life, but that are then secondarily selected for their protective effects against dementia and other aging-related diseases,” said Gagneux.
Co-authors include: Sudeshna Saha, Naazneen Khan, Andrea Verhagen, Aniruddha Sasmal and Sandra Diaz at UC San Diego, Troy Comi and Joshua M. Akey at Princeton University, Hai Yu and Xi Chen at UC Davis, and Martin Frank at Biognos AB.
See also
Funding: This work was funded by the National Institutes of Health (grant R01GM32373) and the Cure Alzheimer’s Fund.
About this genetics and evolutionary neuroscience research news
Author: Scott La Fee
Source: UCSD
Contact: Scott La Fee – UCSD
Image: The image is credited to NIH
Original Research: Open access.
“Evolution of Human-specific Alleles Protecting Cognitive Function of Grandmothers” by Ajit Varki et al. Molecular Biology and Evolution
Abstract
Evolution of Human-specific Alleles Protecting Cognitive Function of Grandmothers
The myelomonocytic receptor CD33 (Siglec-3) inhibits innate immune reactivity by extracellular V-set domain recognition of sialic acid (Sia)-containing “self-associated molecular patterns” (SAMPs). We earlier showed that V-set domain-deficient CD33-variant allele, protective against late-onset Alzheimer’s Disease (LOAD), is derived and specific to the hominin-lineage.
We now report multiple hominin-specific CD33 V-set domain mutations. Due to hominin-specific, fixed loss-of-function mutation in the CMAH gene, humans lack N-glycolylneuraminic acid (Neu5Gc), the preferred Sia-ligand of ancestral CD33. Mutational analysis and MD-simulations indicate that fixed change in amino acid 21 of hominin V-set domain and conformational changes related to His45 corrected for Neu5Gc-loss by switching to N-acetylneuraminic acid (Neu5Ac)-recognition.
We show that human-specific pathogens Neisseria gonorrhoeae and Group B Streptococcus selectively bind huCD33 as part of immune evasive molecular mimicry of host SAMPs and that this binding is significantly impacted by amino acid 21 modification.
In addition to LOAD-protective CD33 alleles, humans harbor derived, population-universal, cognition-protective variants at several other loci. Interestingly, 11 of 13 SNPs in these human genes (including CD33) are not shared by genomes of archaic hominins: Neanderthals and Denisovans.
We present a plausible evolutionary scenario to compile, correlate and comprehend existing knowledge about huCD33-evolution and suggest that grandmothering emerged in humans.
Did gonorrhea give us grandparents?
Researchers at University of California San Diego School of Medicine previously found a set of human gene mutations that protect older adults against cognitive decline and dementia. In a new study, published July 9, 2022 in Molecular Biology and Evolution, they focus on one of these mutated genes and attempt to trace its evolution—when and why it appeared in the human genome. The findings suggest selective pressure from infectious pathogens like gonorrhea may have promoted the emergence of this gene variant in Homo sapiens, and inadvertently supported the existence of grandparents in human society.
The biology of most animal species is optimized for reproduction, often at the expense of future health and longer lifespans. In fact, humans are one of the only species known to live well past menopause. According to the “grandmother hypothesis,” this is because older women provide important support in raising human infants and children, who require more care than the young of other species. Scientists are now trying to understand what features of human biology make this longer-term health possible.
When researchers previously compared human and chimpanzee genomes, they found that humans have a unique version of the gene for CD33, a receptor expressed in immune cells. The standard CD33 receptor binds to a type of sugar called sialic acid that all human cells are coated with. When the immune cell senses the sialic acid via CD33, it recognizes the other cell as part of the body and does not attack it, preventing an autoimmune response.
The CD33 receptor is also expressed in brain immune cells called microglia, where it helps control neuroinflammation. However, microglia also have an important role in clearing away damaged brain cells and amyloid plaques associated with Alzheimer’s disease. By binding to the sialic acids on these cells and plaques, regular CD33 receptors actually suppress this important microglial function and increase the risk of dementia.
This is where the new gene variant comes in. Somewhere along the evolutionary line, humans picked up an additional mutated form of CD33 that is missing the sugar-binding site. The mutated receptor no longer reacts to sialic acids on damaged cells and plaques, allowing the microglia to break them down. Indeed, higher levels of this CD33 variant were independently found to be protective against late-onset Alzheimer’s.
In trying to understand when this gene variant first emerged, co-senior author Ajit Varki, MD, Distinguished Professor of Medicine and Cellular and Molecular Medicine at UC San Diego School of Medicine, and colleagues found evidence of strong positive selection, suggesting something was driving the gene to evolve more rapidly than expected. They also discovered that this particular version of CD33 was not present in the genomes of Neanderthals or Denisovans, our closest evolutionary relatives.
“For most genes that are different in humans and chimps, Neanderthals usually have the same version as the humans, so this was really surprising to us,” said Varki. “These findings suggest the wisdom and care of healthy grandparents may have been an important evolutionary advantage that we had over other ancient hominin species.”
Varki led the study with Pascal Gagneux, Ph.D., professor of pathology at UC San Diego School of Medicine and professor in the Department of Anthropology. The authors said the study provides new evidence supporting the grandmother hypothesis.
Still, evolutionary theory says reproductive success is the main driver of genetic selection, not post-reproductive cognitive health. So what was pushing the prevalence of this mutated form of CD33 in humans?
One possibility, suggest the authors, is that highly infectious diseases like gonorrhea, which can be detrimental to reproductive health, might have impacted human evolution. Gonorrhea bacteria coat themselves in the same sugars that CD33 receptors bind to. Like a wolf in sheep’s clothing, the bacteria are able to trick human immune cells to not identify them as outside invaders.
The researchers suggest that the mutated version of CD33 without a sugar-binding site emerged as a human adaptation against such “molecular mimicry” by gonorrhea and other pathogens. Indeed, they confirmed that one of the human-specific mutations was able to completely abolish the interaction between the bacteria and CD33, which would allow immune cells to attack the bacteria again.
Altogether, the authors believe humans initially inherited the mutated form of CD33 to protect against gonorrhea during reproductive age, and this gene variant was later co-opted by the brain for its benefits against dementia.
“It is possible that CD33 is one of many genes selected for their survival advantages against infectious pathogens early in life, but that are then secondarily selected for their protective effects against dementia and other aging-related diseases,” said Gagneux.
Co-authors include Sudeshna Saha, Naazneen Khan, Andrea Verhagen, Aniruddha Sasmal and Sandra Diaz at UC San Diego; Troy Comi and Joshua M. Akey at Princeton University; Hai Yu and Xi Chen at UC Davis, and Martin Frank at Biognos AB.
How a protein in your brain could protect against Alzheimer’s disease
More information:
Sudeshna Saha et al, Evolution of Human-specific Alleles Protecting Cognitive Function of Grandmothers, Molecular Biology and Evolution (2022). DOI: 10.1093/molbev/msac151
Sudeshna Saha et al, Evolution of Human-specific Alleles Protecting Cognitive Function of Grandmothers, Molecular Biology and Evolution (2022). DOI: 10.1093/molbev/msac151
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Looking after grandchildren won’t make you feel younger, study suggests | Grandparents and grandparenting
Grandparents planning hefty amounts of childcare this half-term might want to think again after research claimed to disprove previous findings of a “rejuvenating effect” from looking after grandchildren.
Many studies have appeared to show mental and physical health advantages for those who care for their grandchildren. But none involved researchers talking to the same grandparents before and after their caregiving responsibilities began.
When the authors of Is There a Rejuvenating Effect of (Grand)Childcare? A Longitudinal Study, published this week in The Journals of Gerontology, did that, they found that caring for grandchildren failed to make grandparents feel any younger than their actual age.
The age people feel they are – as opposed to the age on their birth certificate – is seen as a strong indicator of their mental and physical wellbeing, sometimes even outperforming chronological age as a direct predictor of psychological and health-related outcomes, including risk of death.
“This is the first study to look at the same people before and after taking up grandparental childcare in terms of the effects on subjective age,” said Dr Valeria Bordone, co-author of the report.
Bordone is also co-author of a 2016 report, Do Grandchildren Influence How Old You Feel? That found over-65s who take care of grandchildren feel at least two years younger than their age, rising to 2.6 years for men aged 74-85.
But her new findings have given her pause for thought. “Contrary to our 2016 findings, our new study found no youthful effect of the transition from not being a caregiver to becoming a grandchild caregiver for either grandfathers or grandmothers,” she said.
The new study was welcomed by Prof Cecilia Tomassini, a leading member of the Grandparenting in Europe network of researchers.
“This research adds important insight to a question that hasn’t previously been interrogated by going back to the same people,” she said. “Even studies that have gone back to the same group have tended to lose sight of grandparents in ill health because they’ve dropped out of the research. This means those papers have ended up by only looking at healthy grandparents, which is why they’ve been getting, until now, largely positive responses.”
Bordone now believes that attributing a causal effect between childcare provision and feeling younger is wrong. Instead, she said, the link is likely to have more to do with hidden selection effects. “It may well be that personality traits and family values that mean grandparents already have a young, subjective age are overrepresented among individuals who provide care to others,” she said.
In short, rather than childcare making grandparents feel young, it’s the grandparents who feel young already who do more childcare.
When Bordone researched this issue in 2016, she asked adults who care for their grandchildren how young and healthy they felt. This time, she questioned the same 7,730 adults aged 50–85 before they began childcare. Returning over a period of time during which 21% started providing childcare, she asked the same question. Those who never provided childcare remained in the control group.
If your children’s grandparents are now reluctant to step up this half-term, you might have more luck asking a friend or neighbour of grandparent age.
The research threw up the unexpected finding that there are slight benefits in older adults looking after young children who are not their own kin. The hypothesis, said Bordone, is that unrelated children bring with them the rejuvenating effect of youth – without the same reminder of old age that grandchildren do.
“Grandparenthood is a powerful reminder of a person’s ageing and as such it is likely to affect subjective age,” she said.
Coronavirus Updates: Restrictions to be lifted on fully-vaccinated, non-American travelers Monday
NEW YORK (WABC) — The U.S. is lifting restrictions on foreign travelers who are fully vaccinated against COVID, starting Monday.
The Biden administration is expecting long lines and delays at airports with travelers possibly pouring into the states.
When the announcement was made, online searches for international flights jumped 338%.
Delta Airlines saw bookings shoot up by 450%, and United Airlines says it will be bringing 30,000 travelers into the U.S. on Monday alone.
Here are more of today’s COVID-19 headlines:
Novavax says its vaccine could win over skeptics
The biotechnology company Novavax plans to submit complete data to the US Food and Drug Administration soon for possible emergency use authorization of its coronavirus vaccine, CEO Stanley Erck told CNN in a phone interview Friday. Novavax’s vaccine, called NVX-CoV2373, is made using somewhat more conventional methods than the vaccines already authorized for use in the US.
US cancels vaccine maker’s multimillion dollar deal
The federal government has canceled a multimillion dollar deal with Emergent BioSolutions, a Maryland-based vaccine manufacturer with facilities in Baltimore that were found to have produced millions of contaminated Johnson & Johnson vaccine doses this spring, the Washington Post reported. Emergent disclosed the development Thursday in a conference call discussing its latest financial results, the Post reported. Emergent said it will forgo about $180 million due to the contract’s termination, according to the Post. Emergent BioSolutions played a role in the Trump administration’s effort to speed up vaccine development and distribution. But after winning a contract from the previous administration, Emergent quickly ran into production problems. In March, ingredients intended for use in producing the Oxford-AstraZeneca vaccine shots contaminated 15 million doses of the Johnson & Johnson vaccine. The problems with the vaccines caused a monthslong delay in production. After that, the Biden administration put Johnson & Johnson in direct control of vaccine production there.
15 unions reach COVID vaccine mandate deal with NYC, talks continue with outliers
New York City employees who don’t want to get vaccinated have until Friday to file for a religious or medical exemption if they have any hope of staying on the payroll, this as the city announces more deals with unions representing municipal workers. Mayor Bill de Blasio said Friday that 15 unions, including city’s largest, DC 37, have signed onto the deal. The unions represent more than 100,000 city workers covered by this most recent mandate that took effect last week, but the police and fire unions are not included and are still trying to hash out their own deals. Around 92% of city workers under the mandate are vaccinated, including 90% of EMS, 79% of firefighters, 85% of sanitation workers, and 85% of NYPD employees.
COVID vaccine refusal 10th highest reason for job cuts in 2021, report says
While experts say we’re still in the so-called “Great Resignation,” a recent Jobs Cut Report uncovered vaccine refusal as the 10th highest reason for job cuts this year. Numbers released by Chicago-based outplacement and business and executive coaching firm Challenger, Gray & Christmas, Inc. came on on the same day President Biden announced new federal guidance and deadline for tens of millions of workers to get vaccinated.
“Roughly 5,000 people that lost their jobs in the last month due to COVID vaccine refusal made up actually 22% of the total number of people that we tracked being let go across the country,” the firm’s Senior VP Andy Challenger told our sister station KGO-TV.
Pfizer’s COVID-19 pill reduces risk of being hospitalized or dying by 89%, company says
A course of pills developed by Pfizer can slash the risk of being hospitalized or dying from COVID-19 by 89% if taken within three days of developing symptoms, according to results released Friday by the pharmaceutical company. In a study of more than 1,200 COVID-19 patients with a higher risk of developing serious illness, people who took Pfizer’s pills were far less likely to end up in the hospital compared to people who got placebo pills. None of the people who got the real pills died, but 10 people who got placebo pills died, according to results summarized in a Pfizer press release.
SantaCon returns
After taking a year off due to the pandemic, SantaCon is returning to New York City. The event requires a $13 donation for all-inclusive Santa Badge access to the official SantaCon venues. The location of a Yuletide kickoff party won’t be disclosed until closer to the December 11 SantaCon date.
Turkey Day troubles? Smaller birds, popular Thanksgiving sides could be harder to find in 2021
Consumers may have to trim their list of trimmings for their highly anticipated Thanksgiving meal this year. Top turkey seller Butterball said it doesn’t expect an overall gobbler shortage, but that those in search of a smaller size bird could have a hard time.
“Typically a 10- to 12-pound (turkey) up to 14 pounds is going to be more difficult,” Butterball CEO Jay Jandrain told “Good Morning America” on Friday. “Anything over 16 pounds, they’ll certainly be more readily available.”
Q&A: What to know about COVID-19 vaccines for kids aged 5-11
Vaccinations finally are available to U.S. children as young as 5, to the relief of some parents even as others have questions or fears. Late Tuesday, the Centers for Disease Control and Prevention gave the final OK for youngsters age 5 to 11 to get kid-size doses of the vaccine made by Pfizer and its partner BioNTech. Pediatricians and other doctors’ groups praised the move and are gearing up to help families decide whether to vaccinate their children. The shots could be available as soon as Wednesday and will be offered at pediatricians offices, clinics and pharmacies. Like COVID-19 vaccines for adults, they are free. Here’s everything you need to know.
Will the supply chain issues impact holiday shopping? Here’s what the experts say
With the holiday shopping suddenly upon us, it appears that getting that perfect gift or preparing that perfect meal will be far more challenging than in years past due to supply chain issues. Shoppers are noticing that it’s difficult to find a variety of items, and virtually everything from food to Christmas trees are more expensive. The price increase is being caused by gridlock at major seaports and a truck driver shortage across the country. Analysts say the forecast for the holiday season is not looking better.
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Global study estimates 1.5 million children lost parents or grandparents to Covid-19
“Covid-19 has created this urgent crisis affecting children in almost every nation,” Dr. Susan Hillis of the U.S. Centers for Disease Control and Prevention COVID-19 Response Team, who worked on the study, told CNN.
“For every two Covid-19 deaths, one child faces the death of a parent or caregiver.”
The team — including researchers from the CDC, USAID, the World Bank, University College London and elsewhere — counted deaths in 21 countries that accounted for more than 76% of all Covid cases. They used methods developed and validated years ago to estimate the number of children globally who would have been orphaned by AIDS to forecast the number of Covid-19 orphans.
“Globally, from March 1, 2020, to April 30, 2021, we estimate 1,134,000 children experienced the death of primary caregivers, including at least one parent or custodial grandparent,” they wrote in a report published in the Lancet medical journal. Plus, they added, “1,562,000 children experienced the death of at least one primary or secondary caregiver.”
Kids who lose a parent or caregiver are not only immediately stressed; they are also more likely to suffer diseases themselves, to be abused, and to suffer poverty, the researchers said.
“There are very severe consequences,” Hillis said. “The consequences of all these adversities are often lifelong,” she added.
“Children losing primary caregivers have higher risks of experiencing mental health problems; physical, emotional, and sexual violence; and family poverty,” the team wrote. “These adverse experiences raise risks of suicide, adolescent pregnancy, infectious diseases including HIV/ AIDS, and chronic diseases.”
Grandparents are more important than might initially be evident, they added. “In the USA, 40% of grandparents living with grandchildren serve as their primary caregivers; in the UK, 40% of grandparents provide regular care for grandchildren,” the researchers wrote.
Losing a grandparent can be more than merely upsetting. “The death of grandparents can also reduce the psychosocial, practical, and/or financial support for their grandchildren,” the researchers wrote in a linked online report. “These types of vulnerabilities often place children in need of alternative or supplementary care, such as kinship or foster care.”
But the pandemic has damaged the ability to provide even this less-than-desirable level of care for kids. “However, public health responses to the pandemic, such as stay-at-home orders and the constraints of conducting child protection evaluations remotely, have severely reduced the capacity of established child protection systems and services to provide much needed child safety interventions and support,” the report reads.
“These 1.5 million children are the tragic overlooked consequence of the more than 3 million COVID-19-associated deaths by April 30, 2021,” the researchers added. “Orphanhood and caregiver deaths are a hidden pandemic resulting from COVID-19-associated deaths.”
What to do about it? Number one, the researchers recommend: get Covid-19 vaccines to everyone as quickly as possible, and help prevent infections in other ways including mask use and distancing.
“As soon as a primary caregiver becomes seriously ill with COVID-19, or a family becomes seriously impacted by other pandemic-associated factors, that family should receive comprehensive evaluation including testing, tracing, and appropriate and supported quarantine of exposed family members. The family should be supported in developing a plan for how children might be cared for if their caregiver were to die,” they added.
And societies need to help families affected by the pandemic with economic, educational and mental health support, the report recommends.
Low-cost services to provide all these are already available and there’s evidence to support what works, the researchers said.