Sperm counts of men in North America, Europe, Australia and New Zealand are plunging, according to a new analysis published Tuesday.
Sperm counts of men in North America, Europe, Australia and New Zealand are plunging, according to a new analysis published Tuesday.
A group of scientists in Oregon has successfully modified the genes of embryos using CRISPR, a cut-and-paste gene-editing tool.
The experiments, which have not yet been subject to peer review, were conducted by biologist Shoukhrat Mitalipov and colleagues at Oregon Health & Science University in Portland, MIT Technology Review reported. Mitalipov conducted the experiments on dozens of single-celled embryos, which were discarded before they could progress very far in development, according to Technology Review. This is the first time that scientists in the United States have used this approach to edit the genes of embryos.
The CRISPR/Cas9 gene-editing system is a simple “cut and replace” method for editing precise spots on the genome. CRISPRS are long stretches of DNA that are recognized by molecular “scissors” called Cas9; by inserting CRISPR DNA near target DNA, scientists can theoretically tell Cas9 to cut anywhere in the genome. Scientists can then swap a replacement gene sequence in the place of the snipped sequence. The replacement sequence then gets automatically incorporated into the genome by natural DNA repair mechanisms.
In 2015, a group in China used CRISPR to edit several human embryos that had severe defects, though none were allowed to gestate very long before being discarded. If rumors are to be believed, the new results are more promising than those earlier efforts, according to Technology Review. The Chinese technique led to genetic changes in some, but not all of the cells in the embryos, and CRISPR sometimes snipped out the wrong place in the DNA. According to Technology Review, the new technique was used in dozens of embryos that were created for in vitro fertilization (IVF), using the sperm of men who had severe genetic defects.
In general, editing the germ line — meaning sperm, eggs or embryos — has been controversial, because it means permanently changing the DNA that is passed on from one generation to the next. Some scientists have called for a ban on germ-line editing, saying the approach is incredibly risky and ethically dubious.
The adhesive, described today (July 27) in a new study in the journal Science, sticks to wet surfaces, including the surface of a beating heart. It isn’t toxic to cells, which gives it an advantage over many surgical glues. It’s not available in operating rooms just yet — its developers say that could take years — but it could potentially be approved much more quickly for applications such as closing skin wounds.
The slug-inspired glue is “very stretchy and very tough,” said Jianyu Li, a postdoctoral researcher at Harvard University’s Wyss Institute for Biologically Inspired Engineering and the lead author of the study. Li and his colleagues applied the adhesive to a blood-soaked, beating pig heart and found that it worked better than any other surgical glue on the market.
The inspiration for the glue came from Arion subfuscus, a large and slimy species of slug found in North America and western Europe. These slugs excrete a sticky, yellow-orange slime that adheres well to wet surfaces.
That characteristic intrigued Li and his colleagues, and they set to work making an artificial version of the slime. The key, Li told Live Science, is that the slime is made up of long, straight chains of molecules called polymers, which are also bound to each other — a phenomenon called cross-linking. Cross-linking makes materials strong, but the slug slime has the added advantage of having two types of cross-link bonds. Some were covalent bonds, which means they hold molecules together by sharing electrons. Others were ionic bonds, meaning one molecule hands over its electrons to another. These “hybridized” cross-links make the slug mucusboth tough and stretchy, Li said.
The team mimicked this structure using artificial polymers layered onto what they called a “dissipative matrix.” The polymers provide the sticking power, Li explained, while the dissipative-matrix layer acts like a shock absorber: It can stretch and deform without rupturing.
To test the glue, the researchers applied it to pig skin, cartilage, arteries, liver tissue and hearts — including hearts that were inflated with water or air and covered in blood. The material proved extremely stretchable, expanding 14 times its original length without ever breaking loose from the liver tissue. When used to patch a hole in a pig heart, the adhesive maintained its seal even when it was stretched to twice its original length tens of thousands of times, at pressures exceeding normal human blood pressure.
The researchers even applied the adhesive to the beating heart of a real pig and found that the adhesion to the dancing, bloody surface was about eight times as strong as the adhesion of any commercially available surgical glue.
The glue was also tested in a living rat: The researchers simulated an emergency surgery by slicing the rats’ liver tissue and then patching the wound with either the glue or a standard blood-staunching product called Surgiflo. They found that the new adhesive was as good at stopping the blood flow as the standard glue; the rats treated with the new glue experienced no additional hemorrhaging up to two weeks after the surgery. The Surgiflo-treated rats, however, sometimes suffered from tissue death and scar tissue, the researchers reported. The rats treated with the slime-inspired glue did not experience these side effects.
Whether the new glue makes it to the operating room depends on much more extensive clinical testing, Li said, but the adhesive could make its debut as a new method of dressing external wounds on a shorter timeline than that.
“We have a company working on trying to push our material to clinical applications, and we have a patent pending,” Li said.
The announcement by researchers in Portland, Oregon that they’ve successfully modified the genetic material of a human embryo took some people by surprise.
With headlines referring to “groundbreaking” research and “designer babies,” you might wonder what the scientists actually accomplished. This was a big step forward, but hardly unexpected. As this kind of work proceeds, it continues to raise questions about ethical issues and how we should we react.
For a number of years now we have had the ability to alter genetic material in a cell, using a technique called CRISPR.
The DNA that makes up our genome comprises long sequences of base pairs, each base indicated by one of four letters. These letters form a genetic alphabet, and the “words” or “sentences” created from a particular order of letters are the genes that determine our characteristics.
Sometimes words can be “misspelled” or sentences slightly garbled, resulting in a disease or disorder. Genetic engineering is designed to correct those mistakes. CRISPR is a tool that enables scientists to target a specific area of a gene, working like the search-and-replace function in Microsoft Word, to remove a section and insert the “correct” sequence.
In the last decade, CRISPR has been the primary tool for those seeking to modify genes – human and otherwise. Among other things, it has been used in experiments to make mosquitoes resistant to malaria, genetically modify plants to be resistant to disease, explore the possibility of engineered pets and livestock, and potentially treat some human diseases (including HIV, hemophilia and leukemia).
Up until recently, the focus in humans has been on changing the cells of a single individual, and not changing eggs, sperm and early embryos – what are called the “germline” cells that pass traits along to offspring. The theory is that focusing on non-germline cells would limit any unexpected long-term impact of genetic changes on descendants. At the same time, this limitation means that we would have to use the technique in every generation, which affects its potential therapeutic benefit.
Earlier this year, an international committee convened by the National Academy of Sciences issued a report that, while highlighting the concerns with human germline genetic engineering, laid out a series of safeguards and recommended oversight. The report was widely regarded as opening the door to embryo-editing research.
That is exactly what happened in Oregon. Although this is the first study reported in the United States, similar research has been conducted in China. This new study, however, apparently avoided previous errors we’ve seen with CRISPR – such as changes in other, untargeted parts of the genome, or the desired change not occurring in all cells. Both of these problems had made scientists wary of using CRISPR to make changes in embryos that might eventually be used in a human pregnancy. Evidence of more successful (and thus safer) CRISPR use may lead to additional studies involving human embryos.
First, this study did not entail the creation of “designer babies,” despite some news headlines. The research involved only early stage embryos, outside the womb, none of which was allowed to develop beyond a few days.
In fact, there are a number of existing limits – both policy-based and scientific – that will create barriers to implanting an edited embryo to achieve the birth of a child. There is a federal ban on funding gene editing research in embryos; in some states, there are also total bans on embryo research, regardless of how funded. In addition, the implantation of an edited human embryos would be regulated under the federal human research regulations, the Food, Drug and Cosmetic Act and potentially the federal rules regarding clinical laboratory testing.
Beyond the regulatory barriers, we are a long way from having the scientific knowledge necessary to design our children. While the Oregon experiment focused on a single gene correction to inherited diseases, there are few human traits that are controlled by one gene. Anything that involves multiple genes or a gene/environment interaction will be less amenable to this type of engineering. Most characteristics we might be interested in designing – such as intelligence, personality, athletic or artistic or musical ability – are much more complex.
Second, while this is a significant step forward in the science regarding the use of the CRISPR technique, it is only one step. There is a long way to go between this and a cure for various disease and disorders. This is not to say that there aren’t concerns. But we have some time to consider the issues before the use of the technique becomes a mainstream medical practice.
Taking into account the cautions above, we do need to decide when and how we should use this technique.
Should there be limits on the types of things you can edit in an embryo? If so, what should they entail? These questions also involve deciding who gets to set the limits and control access to the technology.
We may also be concerned about who gets to control the subsequent research using this technology. Should there be state or federal oversight? Keep in mind that we cannot control what happens in other countries. Even in this country it can be difficult to craft guidelines that restrict only the research someone finds objectionable, while allowing other important research to continue. Additionally, the use of assisted reproductive technologies (IVF, for example) is largely unregulated in the U.S., and the decision to put in place restrictions will certainly raise objections from both potential parents and IVF providers.
Moreover, there are important questions about cost and access. Right now most assisted reproductive technologies are available only to higher-income individuals. A handful of states mandate infertility treatment coverage, but it is very limited. How should we regulate access to embryo editing for serious diseases? We are in the midst of a widespread debateabout health care, access and cost. If it becomes established and safe, should this technique be part of a basic package of health care services when used to help create a child who does not suffer from a specific genetic problem? What about editing for nonhealth issues or less serious problems – are there fairness concerns if only people with sufficient wealth can access?
So far the promise of genetic engineering for disease eradication has not lived up to its hype. Nor have many other milestones, like the 1996 cloning of Dolly the sheep, resulted in the feared apocalypse. The announcement of the Oregon study is only the next step in a long line of research. Nonetheless, it is sure to bring many of the issues about embryos, stem cell research, genetic engineering and reproductive technologies back into the spotlight. Now is the time to figure out how we want to see this gene-editing path unfold.
The U.S. Food and Drug Administration aims to reduce nicotine levels in cigarettes while exploring measures to move smokers toward e-cigarettes, in a major regulatory shift announced on Friday that sent traditional cigarette company stocks plunging.
The move means FDA Commissioner Scott Gottlieb has thrown his regulatory weight on the side of those advocating for e-cigarettes in the debate over whether they potentially hold some public health benefits.
Shares of major tobacco companies in the United States and UK slumped in heavy trading volume, with the world’s biggest producers poised to lose about $60 billion of market value.
The FDA’s move extends the timeline for applications for new e-cigarette clearance by the FDA to Aug. 8, 2022, giving e-cigarette companies more time to keep their products on the market before the agency goes into the process of final review. It also gives the FDA more time to set the proper framework for regulating e-cigarettes.
“It’s hard to overstate what this could mean for the companies affected: non-addictive levels of nicotine would likely mean a lot fewer smokers and of those people who do still light up, smoking a lot less,” said Neil Wilson, a senior market analyst with ETX Capital in London.
“This is just the U.S. regulator acting but we can easily see others, particularly in Europe, where regulatory pressures are already extremely high, following suit,” Wilson said.
British American Tobacco shares, trading close to all-time highs, fell as much as 11 percent and were on track for their biggest one-day loss in nearly 18 years.
Altria, which makes the Marlboro brand of cigarettes, fell as much as 16 percent, slipping into the red for the year
It’s not every day that medical studies say alcohol could be good for you. People who drink moderately often have a lower risk of developing diabetes than those who never drink, according to a new study published in Diabetologia, the journal of the European Association for the Study of Diabetes.
Ten years is a long time for any trend to stay relevant, not least a hairstyle. But this year it will be a full decade since the “dip-dye” caught on with a certain type of fashion-conscious woman – think models such as Charlotte Free or the singer M.I.A. However, now that Kim Kardashian has adopted the two-tone look, it seems set to become one of the defining hairstyles of the age.
A dip-dye involves leaving the roots undyed, or dark, and the ends bleached or coloured. “That whole two-tone look has evolved quite a bit,” explains Alex Brownsell, founder of the London salon Bleach, who arguably invented the dip-dye as we know it. “The first five years we did it, it was shocking. Now it’s fashion-conscious, but it’s not a trend any more.” Her comments may be damning on one level, but are perhaps more indicative of the way the undyed-roots/dyed-ends look has moved firmly into the mainstream. Zoella, Katy Perry and Lady Gaga have all dabbled in the trend.
For the past few years dyeing has trumped cuts as the cheaper, less permanent way to change your look, says Brownsell – pink hair (very 2008), grey hair (2010, and now resurgent among men) and multi-coloured hair (thanks last year to model Georgia May Jagger) have all had their moments.
But perhaps in reaction to that proliferation of dyed hair, Brownsell thinks that “the cut is coming back among young women. Dip-dyes have become mainstream in the sense that they’re national. It used to be a London thing; now it’s everywhere,” she says. “That said, I don’t think we’ve had anything that has come close to trumping it, and I can’t see it happening for a while.”
Samantha Cusick, a colourist at Taylor Taylor in Shoreditch, east London, says she has seen a shift in the past five years from dip-dyes to balayage, a subtler, more natural take on two-tone colour that derives from the French word to sweep or paint. Its popularity has grown, she thinks, because it lends itself to more bespoke styles. Bleach’s Instagram, which acts as a sort of stylebook of colour trends, has more than 250,000 followers. Cusick’s own has almost 25,000. “It is mainstream, but that isn’t a bad thing,” she says.
With its undyed roots and washed-out ends, the dip-dye look suggests fashion has reverted to that done/undone look that mirrors that other hipster-turned-mainstream favourite, the beard.
But why has the dip-dye, undeniable fashion shorthand for the female hipster, not met with the same level of derision as the beard? Aesthetically speaking, they are poles apart, but both looks suggest a lax approach to vanity, even though both are high-maintenance. Two years ago, researchers declared that “peak beard” had been reached. “It appears that beards gain an advantage when rare, but when they are in fashion and common they are declared ‘trendy’ and that attractiveness is over,” researcher Robert Brooks says. Yet the dip-dye has become mainstream while remaining an acceptable fashion statement.
Perhaps it is because of the tendency to fixate on men when talking about the much-derided notion of hipster fashion. “When you write hipster, everyone immediately knows what – or who – you’re talking about. And it’s always, always a man,” says culture journalist Leonie Cooper. “Men still have such a limited pool to draw from when it comes to fashion. Women have always had permission to be more extravagant and outlandish.” Cooper thinks it’s down to the range of trends available to women: “There’s so much women can draw from in terms of style, hair included.
“But if a man suddenly decides to start wearing a 1940s three-piece suit or a James Dean white T-shirt and trousers, he’s suddenly doing ‘a look’ and opening himself up to ridicule. I don’t think men are as open to chatting about their style as women are presumed to be.”
But if the fate of the beard is anything to go by, the dip-dye hairstyle may soon move into the realms of parody, with Kardashian’s belated adoption ringing its death knell.
Sleep problems in young adults, especially women, are significantly linked to chronic pain and even worsening pain severity over time, researchers report. Overall, 38 percent of young adults with severe sleep problems at initial evaluation had chronic pain at follow-up, compared with 14 percent of those without initial sleep problems.
Early identification and treatment of sleep problems may help reduce later problems with musculoskeletal, headache and abdominal pain in young adults.
“In contrast, the presence of pain generally doesn’t predict worsening sleep problems during the transition between adolescence and young adulthood,” said Dr Irma J Bonvanie from University of Groningen, the Netherlands.
The team analysed relationship between sleep problems and pain in nearly 1,750 young adults in the age group 19-22. The study, published in the journal PAIN, focused on overall chronic pain as well as specific types of pain: musculoskeletal, headache and abdominal pain.
The long-term associations between sleep problems and the pain types were compared between the sexes and the mediating effects of anxiety and depression, fatigue and physical activity were explored. The results suggested that the relationship between sleep problems and pain was stronger in women than men — a difference that may start around older adolescence/emerging adulthood.
Three years later, those with sleep problems were more likely to have new or persistent chronic pain. People with sleep problems were more likely to have chronic pain and had more severe musculoskeletal, headache and abdominal pain.
Women’s health concerns are a little different from those of men. If you’re a woman, these tips will soon have you feeling fit and energetic. Here are six simple things that women can do every day (or with regularity) to ensure good health:
1: Eat a healthy diet. “You want to eat as close to a natural foods diet as you can,” says Donald Novey, MD, an integrative medicine physician with the Advocate Medical Group in Park Ridge, Ill. That means a variety of fresh fruits and vegetables and fewer processed foods. Eat whole grains and high-fiber foods and choose leaner cuts of meat, fish, and poultry. Include low-fat dairy products in your diet as well — depending on your age, you need between 800 and 1,500 milligrams of calcium daily to help avoid osteoporosis, Dr. Novey says. Avoid foods and beverages that are high in calories, sugar, salt, and fat.
Healthy eating will help you maintain a proper weight for your height, which is important because being overweight can lead to a number of illnesses. Looking for a healthy snack? Try some raw vegetables, such as celery, carrots, broccoli, cucumbers, or zucchini with dip made from low-fat yogurt.
If you’re not getting enough vitamins and nutrients in your diet, you might want to take a multivitamin and a calcium supplement to make sure you’re maintaining good health.
2: Exercise. Heart disease is the leading cause of death among women in America, but plenty of exercise can help keep your heart healthy. You want to exercise at least 30 minutes a day, five days a week, if not every day. Aerobic exercises (walking, swimming, jogging, bicycling, dancing) are good for women’s health in general and especially for your heart, says Sabrena Merrill, MS, of Lawrence, Kan., a certified personal trainer and group fitness instructor and a spokeswoman for the American Council on Exercise.
3: Avoid risky habits. Stay away from cigarettes and people who smoke. Don’t use drugs. If you drink alcohol, do so in moderation. Most women’s health studies show that women can safely consume one drink a day. A drink is considered to be about 12 to 14 grams of alcohol, which is equal to 12 ounces of beer (4.5 percent alcohol); 5 ounces of wine (12.9 percent alcohol); or 1.5 ounces of spirits (hard liquor such as gin or whiskey, 80-proof).
4: Manage stress. No matter what stage of her life — daughter, mother, grandmother — a woman often wears many hats and deals with a lot of pressure and stress. “Take a few minutes every day just to relax and get your perspective back again,” Novey says. “It doesn’t take long, and mental health is important to your physical well-being.” You also can manage stress with exercise, relaxation techniques, or meditation.
5: Sun safely. Excessive exposure to the sun’s harmful rays can cause skin cancer, which can be deadly. To protect against skin cancer, wear sunscreen with a sun protection factor (SPF) of at least 15 if you are going to be outdoors for more than a few minutes. Even if you wear sunscreen faithfully, you should check regularly for signs of skin cancer. Warning signs include any changes in the size, shape, color, or feel of birthmarks, moles, or freckles, or new, enlarging, pigmented, or red skin areas. If you spot any changes or you find you have sores that are not healing, consult your doctor.
6: Check for breast cancer. The American Cancer Society no longer recommends monthly breast self-exams for women. However, it still suggests them as “an option” for women, starting in their 20s. You should be on the lookout for any changes in your breasts and report any concerns to your doctor. All women 40 and older should get a yearly mammogram as a mammogram is the most effective way of detecting cancer in its earliest stages, when it is most treatable.
A woman’s health needs change as she ages, but the basics of women’s health remain the same. If you follow these six simple healthy living tips, you will improve your quality of life for years to come.