As a general rule-of-thumb, eukaryotic cells (e.g., amoebae or human body cells) are about 1,000 times bigger than bacteria, and bacteria are about 10-100 times bigger than viruses. But in biology, there is rarely such a thing as an inviolable rule. For example, two types of giant amoeba-infecting viruses, known as Megaviridae and Pandoravirus, are so large that they are comparable to bacteria in terms of physical size and genome length.
Now, after poking around in the Siberian permafrost, a team of French and Russian scientists have reported the discovery of a third. The virus, which they named Pithovirus, resembles a mishmash of the two previously known giant viruses. And remarkably, it is 30,000 years old!
Panel A depicts a close-up of the virus's envelope and inner membrane. The very top of the virus contains what looks like a "cork." Panel B depicts a cross-section and a longitudinal-section, respectively. The arrow points to what appears to be a long, tubular membrane connected to the cork.
Panel C depicts the hexagonal cork, as seen from the top of the virus. (If the cork's tiny holes bother you, perhaps you have trypophobia.)
The most interesting part of the research, though, isn't the discovery of a new virus. Instead, it is that the virus was buried 30,000 years ago and revived when it was cultured in the presence of amoebae, which it promptly infected. The authors ominously warn that previously undisturbed environments -- even ancient ones -- could be sources of emerging infectious diseases for humans and animals.
It should be noted, however, that it's not necessary to dig around in the dirt for scary new viruses. The MERS virus, which has already killed several dozen people, made its global debut in 2012 and is linked to contact with camels. And influenza evolves so rapidly that pandemics are a constant threat.
Still, the authors rightly conclude that their "results thus further substantiate the possibility that infectious viral pathogens might be released from ancient permafrost layers exposed by thawing, mining, or drilling." Indeed, that is a tad unsettling.
Source: Matthieu Legendre et al. "Thirty-thousand-year-old distant relative of giant icosahedral DNA viruses with a pandoravirus morphology." PNAS Early Edition. Published online before print: 3-Mar-2014. doi: 10.1073/pnas.1320670111
The nuclear disaster at Fukushima Daiichi in Japan was perhaps the worst of all time, but despite that ominous reputation, radiation risks to the surrounding population are surprisingly slight.
Even the most affected individuals -- those who remained in highly contaminated towns within the 20-kilometer evacuation zone for four months following the disaster -- only have a faintly higher risk of developing cancer. Last year, the World Health Organization reported a "7% higher risk of leukemia in males exposed as infants, a 6% higher risk of breast cancer in females exposed as infants and a 4% higher risk, overall, of developing solid cancers for females." The WHO also reported that, for girls exposed as infants, 1.25 out of 100 will develop thyroid cancer, compared to the previous rate of 0.75 out of 100.
By comparison, smoking raises the risk of lung cancer by upwards of 2000%.
Now, a new study from a massive team of Japanese researchers shows that for people living more than twenty kilometers from Fukushima Daiichi, the elevated cancer risk is even more diminutive. Their results are published in the Proceedings of the National Academy of Sciences.
483 residents of the village of Kawauchi, the area of Tamano in the city of Soma, and the area of Haramachi in the city of Minamisoma wore dosimeters for two months during the summer of 2012. Radiation rates are naturally highest in the summer, as winter snow tends to act as a shield against terrestrial radiation. To get a complete picture, the researchers also examined radiation levels in another 131 subjects' food, and estimated the inhalation dose rate of radiocesium from aerosols.
When all of those radiation sources were tallied together, the researchers found that the mean annual radiation dose rate in 2012 associated with the accident was between 0.89 – 2.51 millisieverts per year. Those levels are predicted to drop steeply by 2022, to just one-third of current levels.
By comparison, Japanese people are generally exposed to a background radiation of 2.09 millisieverts per year. For that, they can thank a multitude of sources, including cosmic radiation and naturally occurring radon in the soil.
In terms of public health, the radiation exposure from Fukushima Daiichi poses negligible risks to those in the studied areas. Residents of Tamano, where radiation measurements were highest, are predicted to have higher lifetime rates of solid cancer, leukemia, and breast cancer by 1.06%, 0.03% and 0.28%, respectively.
Sadly, the Fukushima-Daiichi disaster has rendered certain areas around the ruined power plant unlivable indefinitely. But thankfully, the overwhelming majority of Japanese people appears to have been spared from any harmful levels of radiation.
A lot of ink has been spilled over who is responsible for the pervasive anti-scientific and technophobic attitudes held by the public. Conservatives blame liberals, liberals blame conservatives, and atheists blame anybody who believes in God. But a new review by Australian researchers Craig Cormick and Lygia Romanach in Trends in Biotechnology suggests the possibility of a completely different, and even counterintuitive, answer: The scientifically disinterested.
The authors first reported on a previous study on climate change that segmented the population into various groups, such as "Alarmed," "Cautious," and "Dismissive." When classified like this, people's beliefs on climate policy were much easier to understand, suggesting that the media's hyperpartisan tendency to label all conservatives or liberals as climate "deniers" or "alarmists," respectively, is rather missing the point. People differ in their attitudes toward science itself, and gaining a better understanding of those population segments is vital for scientific outreach.
The authors then turned their attention to biotechnology. The study they reported on had segmented the population into four groups, based on their answers to a survey on values:
(1) Concerned and disengaged
(2) Risk averse
(3) Cautiously keen
(4) Science fans
Six of the values questions asked showed striking differences between the groups:
As shown above, the group labeled "concerned and disengaged" was the most likely to be concerned about new technology, believe that science causes more problems than it solves, believe that humans should not tamper with nature, feel that technology advances too quickly for them to understand, and believe that humans depend too much on science and not enough on faith.
The authors conclude that the best approach to scientific outreach would be to tailor messages that resonate within these segments. For example, a person who is risk averse may be receptive to a message in which regulation was stressed.
Perhaps because they wanted to be polite (or perhaps because they disagree), the authors do not draw what seems to be an obvious conclusion: People who are disengaged from science probably know very little about it, which means that some of the people who are most loudly opposed to technological advances (e.g., GMOs) are probably scientifically illiterate.
That leads to one more unsettling conclusion: We are allowing our national science policy debates to be partially dominated by people who know almost nothing about science. And who dominates the rest of the debate? As Dr. Cormick indicated in an e-mail to RealClearScience, those who know a lot about GMOs, but intentionally mislead those who do not.
That's quite a disadvantage for the scientific experts.
Source: Craig Cormick and Lygia Malzoni Romanach. "Segmentation studies provide insights to better understanding attitudes towards science and technology." Trends in Biotechnology 32 (3): 114-6 (2014). doi:10.1016/j.tibtech.2013.12.005
Or at least you don't gain as much as you otherwise would.
A wee nip, or two, or three after competition is a common occurrence for college and professional athletes, runners, and intramural -- "beer league" -- sports players. Even gym rats are occasionally known to attend a happy hour post workout. While most have an inkling that boozing after intense physical activity isn't the wisest course of action, a new study published in PLoS ONE apprises us all of precisely how unwise it is. According to a team of Australian exercise scientists, imbibing alcohol after exercise impairs rates of protein synthesis in recovering muscles, a process key to repairing and rebuilding damaged muscles.
In the study, eight physically active young adult males completed a strenuous exercise regimen combining weightlifting, endurance cycling, and interval training on three separate occasions, with each separated by a two-week rest period. After each bout, researchers provided subjects with varying nutrition. In the first instance, subjects received two servings of 25 grams of protein immediately and four hours after exercise. In the second, subjects received the same levels of protein but also were given alcohol. In the third, subjects received carbohydrates instead of protein and were given alcohol. The alcohol dose -- which was intended to mirror levels of binge drinking reported among sports teams -- was administered as such: subjects consumed screwdrivers containing two shots of vodka (hopefully good vodka) every thirty minutes starting one hour after their workouts. So they got pretty hammered. In the non-alcoholic instance, subjects simply drank orange juice every thirty minutes.
Using muscle biopsies and blood draws to gather data, the researchers found that alcohol significantly reduced protein synthesis by 24% and 37% in the alcohol-protein and alcohol-carbohydrate treatments respectively, compared to the protein treatment. (See above graph. "Rest" is the rate of synthesis with no exercise or nutrition treatment whatsoever.) Scientists have previously speculated that alcohol inhibits post-workout protein synthesis, but the current study is the first to gauge the reduction in humans.
"Alcohol ingestion suppresses the anabolic response in skeletal muscle and may therefore impair recovery and adaptation to training and/or subsequent performance," the authors said of the results.
In the long term, "the athlete who binge drinks after training is likely to benefit less from strength training-induced muscle growth," lead researcher John Hawley added.
The researchers briefly expounded upon a theory to account for the impairment.
"Alcohol consumption generates oxidative stress and inflammation and the potential to disrupt endoplasmic reticulum homeostasis," they wrote. The endoplasmic reticulum is an organelle that folds proteins and ships them around the cell.
Something to note: the authors looked at the effects of binge drinking -- not moderate drinking -- on protein synthesis. Moderate alcohol intake likely wouldn't result in such a marked reduction, though that remains to be studied.*
Since most athletes care about their body to some degree, the authors hope that their evidence will prompt them to adopt more moderate drinking practices. Some studies have shown that, while athletes are healthier overall, they are more likely than the general population to drink to excess.
Source: Parr EB, Camera DM, Areta JL, Burke LM, Phillips SM, et al. (2014) Alcohol Ingestion Impairs Maximal Post-Exercise Rates of Myofibrillar Protein Synthesis following a Single Bout of Concurrent Training. PLoS ONE 9(2): e88384. doi:10.1371/journal.pone.0088384
*Section added 2/21
Last year, Karin Frick and Detlef Guertler of the Gottlieb Duttweiler Institute and Peter Gloor of MIT compiled a list of the top global thought leaders of 2012, thinkers who are shaping current discourse on the present and future states of business and society. Richard Florida, an American urban studies theorist who formed the socioeconomic concept of the Creative Class, topped the first list.
For 2013's rankings, the researchers used Coolhunting software from the company Galaxyadvisors, which tallies the frequency and relevance of citations to assess leaders' influence. The software scoured the blogosphere, comprising writing and videos from sources like TED and YouTube, and Wikipedia entries. Influence indicators were calculated and subsequently averaged into an influence rank, with any ties broken by the number of Google Scholar hits. And now -- drum roll, please -- the top global thought leader of 2013 was...
Even the researchers seemed somewhat surprised.
"With all due respect to the former US vice-president, Oscar winner and Nobel Peace Prize laureate, this is arguably due not so much to the originality of his thought, but instead to his ability to popularise ideas and build bridges between science, politics and society."
Gore's accomplishments are still noteworthy, of course, and apparently have people buzzing. Unlike last year, which didn't really have a clear number one, Gore dominated the competition, scoring ahead of his colleagues on both Wikipedia and in the blogosphere. The former vice president is best known for his work to galvanize the world to take action to stem global climate change.
No rankings of this nature are perfect or completely objective. While the researchers' methods are fairly comprehensive, the biggest drawback of their rankings comes even before they are calculated. Coolhunting software is a network analyzer, and any network first needs nodes. The authors themselves compiled the starting list of 216 thinkers for analysis, defining thought leaders as people "who exercise influence primarily through their words as opposed to their actions." With such an ambiguous definition, many potentials were left out.
"The speculator George Soros is in, because he is also heavily involved in the social debate, while the speculator Warren Buffett is out, because he cares for little else except making money. For us, great journalists like Malcolm Gladwell or Frank Schirrmacher belong to the thinkers, whereas the investigative journalists Julian Assange or Glenn Greenwald do not," the authors explained.
Americans dominated the list. 43 of the top 100 thought leaders were U.S. citizens. Women accounted for 16% of the top 100. Notable thinkers from the realm of science who cracked the top 100 include psychologist Philip Zimbardo (60th), biologist E.O. Wilson (52nd), biologist Richard Dawkins (65th), futurist Ray Kurzweil (46th), anthropologist Jane Goodall (31st), climate scientist James Hansen (24th), physicist Peter Higgs (12th), neurologist Oliver Sacks (11th), and SpaceX owner Elon Musk (6th).
After winning a Nobel Prize in chemistry -- and yet another Nobel Prize for peace -- Linus Pauling's distinguished career took a decidedly undistinguished turn. He began promoting the idea that large doses of vitamin C could greatly reduce colds, cure cancer and improve overall health. To this day, people all over the world start popping vitamin C tablets when they get the sniffles, sadly to no effect. (One study demonstrated, however, that a daily dose of vitamin C could reduce the frequency of colds, but not the duration or severity.)
Yet, despite the general lack of credible scientific evidence to support the idea that people should take daily vitamin supplements, an entire industry has blossomed promoting just that. Unfortunately, the industry is wholeheartedly embraced by practioners of alternative medicine, pseudoscientific quacks who have enormous influence over people's health choices. It is for these reasons that the scientific and medical communities are generally skeptical of (if not outright hostile to) new claims about the benefits of vitamin C or other supplements.
But new research might slightly alter that viewpoint. Last week, the journal Science Translational Medicine published a study that suggests intravenous administration (i.e., injections directly into the blood) of vitamin C -- when provided in combination with chemotherapy -- can help increase the survival time of patients with ovarian cancer. (See figure.)
As shown in Panel C, the fraction of patients who survived for 60 months was greater for the group who received chemotherapy + vitamin C (gray line) than the group who only received chemotherapy (black line). Panel D shows that patients who received vitamin C (right column) had an additional 8.75 months of healthier life. However, due to the small sample size (22 patients total), these results were not statistically significant.
What are we to make of this study? An accompanying commentary by Melanie McConnell and Patries Herst provides some perspective.
First of all, the patients were not eating the vitamin C. The cancer-fighting effect came only from an intravenous injection. The reason is because the concentration of vitamin C needed in the blood to help fight cancer cannot be attained by ingesting vitamin C. Second, vitamin C does not cure cancer by itself; it must be used in combination with traditional chemotherapy. Finally, the commentary states that genetic differences between tumors may mean that vitamin C is not effective at fighting all cancers. Certainly, this study should be followed up with a larger clinical trial.
Though Linus Pauling is still mostly wrong, perhaps the potential therapeutic benefit of vitamin C injections could be magnanimously interpreted as a small step toward rehabilitating his tainted legacy.
Source: Y. Ma, J. Chapman, M. Levine, K. Polireddy, J. Drisko, Q. Chen, High-Dose Parenteral Ascorbate Enhanced Chemosensitivity of Ovarian Cancer and Reduced Toxicity of Chemotherapy. Sci. Transl. Med. 6, 222ra18 (2014).
Commentary: M. J. McConnell, P. M. Herst, Ascorbate Combination Therapy: New Tool in the Anticancer Toolbox?. Sci. Transl. Med. 6, 222fs6 (2014).
One of the big problems with psychology and psychiatry is that diagnosing patients relies heavily upon subjective, qualitative observations instead of more rigorous quantitative methods. In fact, publication of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (known as DSM-5 and colloquially referred to as the "Bible of psychiatry") caused a major controversy precisely because its recommendations made no effort to incorporate biological evidence. A field that refuses to incorporate quantifiable markers of disease is going to have a difficult time gaining credibility.
Thankfully, many in the profession are aware of this problem and are attempting to rectify it. Now, a team of Brazilian researchers has demonstrated that the word patterns a person uses when describing a dream can distinguish between schizophrenia and bipolar disorder, a pair of mental illnesses that are often difficult to tell apart.
The authors interviewed 60 people who were either healthy, schizophrenic or bipolar. They were asked to recount a previous dream. Their responses were transcribed and changed into word graphs. (See panel A in the figure below. Each dot represents a word, and dots were connected based on when the person spoke them.)
As shown in panel B, schizophrenic and bipolar patients displayed strikingly different word graphs from each other and from healthy controls. Schizophrenics tend to discuss their dreams using very few words, while those with bipolar tend to speak excessively and repetitively.
Interestingly, creating word graphs from stories told by the volunteers about a time when they were awake yielded far less useful results. There is something about describing a dream in which the underlying pathologies become much more obvious.
Thus, the authors conclude, "The Freudian notion that 'dreams are the royal road to the unconscious' is clinically useful, after all."
Source: Natália B. Mota et al. "Graph analysis of dream reports is especially informative about psychosis." Scientific Reports 4, Article number: 3691. Published: 15-January-2014. doi:10.1038/srep03691
For the estimated 1.9 million Americans living with a peanut allergy, the simple act of eating out can be a cause of consternation. If even a trace of the nut touches their lips, the immune system unleashes a massive assault on the invading particle. But the reaction is excessive. Imagine if the United States were invaded by a six-year-old child dressed as a bandit armed with a cap gun six-shooter, and defended itself by dropping a nuclear bomb. It would do far more harm than good. In the body, compounds called histamines -- normally beneficial -- are overproduced and wreak havoc, resulting in symptoms such as itchiness, swelling, running nose, watery eyes, coughing, trouble breathing, hives, and even life-threatening anaphylaxis.
For decades, doctors have been working to find ways to diminish or possibly eliminate the allergic response. Of late, a process called immunotherapy, in which the immune system is gradually sensitized to an allergen, has shown promise. Today, a team of researchers from the University of Cambridge report that they've successfully used the therapy to desensitize children to peanut allergy. Their results are published in the prestigious medical journal The Lancet.
Over six months, 49 children were given increasing doses of peanut flour with meals, at increments up to 800mg (about five peanuts), while a control group of 50 children practiced strict avoidance. At the end of the six months, 24 of 39 children in the experimental group (ten either withdrew or were excluded from analysis) could consume a meal containing 1400mg of peanut flour, equivalent to about 10 nuts, with no ill effects. None of the children in the control group showed any improvement with their allergy. However, in phase II of the trial they underwent immunotherapy and enjoyed similar rates of desensitization.
“We think this is fantastic because this is the first study which really shows peanut desensitization works,” lead author Dr. Pamela Ewan told FoxNews.com.
The researchers touted an overall desensitization (defined as the ability to consume ten peanuts per day) rate of 54% at the conclusion of the trial. A more conservative value, to account for the subjects that dropped out or were excluded, is around 50%. However, that's still a significant number, one that will likely be improved upon with further research and honed methods.
In order to maintain desensitization, participants will likely have to regularly consume small doses of peanut, the researchers say. But since immunotherapy research is still in relative infancy, they're not entirely certain.
The researchers stress that immunotherapy should only be attempted in a hospital setting in order to guard against any adverse allergic reactions that might occur.
Source: Ewan, Pamela et. al. "Assessing the efficacy of oral immunotherapy for the desensitisation of peanut allergy in children (STOP II): a phase 2 randomised controlled trial." The Lancet, Early Online Publication, 30 January 2014 doi:10.1016/S0140-6736(13)62301-6
Perhaps thanks to President Bill Clinton, oral sex has been a subject of intense fascination among Americans for the past 15 years. It has long been suspected, and some evidence has suggested, that there was something of an oral sex "epidemic" among younger people a few years ago. Now, a study reported in PLoS ONE helps confirm that the long-standing rumors are probably true.
The data -- broken down by age, race and gender -- is absolutely fascinating. In every age group, white people were significantly more likely to have had oral sex at some point in their lives than people of any other race. The cohort that has the most oral sex is young-ish (age 30-44), white males. (See figure.)
Another point worth noting is that people aged 30-44 -- many of whom came of age during the Clinton Administration -- were likelier to have had oral sex than people aged 45-69. So, quite possibly, the "Clinton-Lewinsky effect" is a very real phenomenon. (Hey, if the President is doing it, why can't we?)
The authors weren't just interested in oral sex patterns, however. They also wanted to know if differences in oral sex behavior are linked to differences in the prevalence of human papillomavirus 16 (HPV16), which itself has been linked to oral and throat cancer. Their epidemiological analysis concluded that the more oral sex partners you have, the likelier you are to acquire HPV16, regardless of age or race.
Oral sex, despite what so many people seem to think, is not a risk-free behavior. Maybe getting an HPV vaccine, wearing a condom, or (gasp!) practicing self-control aren't bad ideas, after all.
Source: D’Souza G, Cullen K, Bowie J, Thorpe R, Fakhry C (2014) Differences in Oral Sexual Behaviors by Gender, Age, and Race Explain Observed Differences in Prevalence of Oral Human Papillomavirus Infection. PLoS ONE 9(1): e86023. doi:10.1371/journal.pone.0086023
Media images strongly impact our perceptions of attractiveness. When we see slender women and muscular men lifted on a pedestal and endlessly fawned over, we're cued to think those forms are ideal.
In general, the majority of men depicted in media outlets are muscular and of a normal weight (though it should be noted that the methods they use to attain extremely lean looks are not always healthy).* The same cannot be said for women. Many female models who grace the pages of magazines and the screens of televisions are underweight. Weighing too little can be just as harmful as being obese. Sufferers contend with malnourishment, fragile bones, fatigue, and weakened immune systems. Moreover, previous studies have found that media images contribute to lower self-esteem, body dissatisfaction, and depressive mood in women.
Many have questioned what level of exposure to these images is required to skew what we perceive as attractive, particularly in regards to weight. According to new research published in PLoS ONE, it may take as little as sixty seconds.
Researchers at the University of Nottingham Campus in Malaysia recruited ninety-five college-aged subjects (46 men, 49 women), split them as evenly as possible into four groups, and exposed each group to 12 images of female models, each viewed for five seconds. One group viewed plus-size models previously rated to be highly attractive, one viewed plus-size models rated as less attractive, one viewed light-weight highly attractive models, and one viewed light-weight less attractive models. After viewing the slideshow, participants looked through manufactured images of a woman whose Body Mass Index (BMI) was subtly altered in each photo and were asked to select which image they deemed to be most attractive.
Men in the four different groups did not differ appreciably in their views on female attractiveness, but women did. When viewing light-weight highly attractive models, female participants rated images with an average BMI of slightly less than 17 as most attractive. (For reference, any BMI under 18.5 is considered underweight for Asians.) However, women who viewed plus-size highly attractive models rated images with an average BMI of 18.4 as most attractive.
"These results... help us to understand how exposure to images of models affects weight preferences of individuals," the researchers say. "Portraying models that are not extremely underweight as being attractive may help change both female and male perceptions of female attractiveness."
A couple key limitations of the study: First, it would have been valuable to see a control group who wasn't exposed to any model images. That way we could see the population's baseline views on attractiveness. Second, the subjects were Asian men and women from the University of Nottingham Campus in Malaysia, so the findings certainly don't extend to all cultures. However, it is refreshing to see a psychology study with subjects who aren't entirely WEIRD (Western, educated, and from industrialized, rich, and democratic countries.)
Source: Stephen ID, Perera AT-M (2014) Judging the Difference between Attractiveness and Health: Does Exposure to Model Images Influence the Judgments Made by Men and Women? PLoS ONE 9(1): e86302. doi:10.1371/journal.pone.0086302
*Passage updated 1/23 to remove what the author realized to be slightly insensitive and overgeneralized statements.