Category Archives: Life Science

Better Health Through: Exercise, Not Smoking, Low Weight, Healthy Diet and Low Alcohol Intake

These 5 activities/state reduce the risk of chronic diseases: regular exercise, not smoking, healthy bodyweight, healthy diet and low alcohol intake. How these were defined

not smoking
body mass index (BMI): 18 to under 25
diet: target was to be 5 portions of fruit and/or vegetables a day, but since almost no one meet that target they reduced the acceptable rate to 3 as accepted as ‘healthy.” Also a diet with less than 30% of calories from fat was required.
physical activity: walking two or more miles to work each day, or cycling ten or more miles to work each day, or ‘vigorous’ exercise described as a regular habit
alcohol: three or fewer units per day, with abstinence not treated as a healthy behaviour.

Healthy Lifestyles Reduce the Incidence of Chronic Diseases and Dementia: Evidence from the Caerphilly Cohort Study (PLoS open science publication).

The numbers of men judged to be following a healthy lifestyle were as follows: 179 (8%) followed none of the five behaviours, 702 (31%) followed one behaviour, 814 (36%) followed two, 429 (19%) followed three, 111 (5%) followed four or five behaviours and only two (0.1%) followed all five behaviors.
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Within a representative sample of middle-aged men, the following of increasing numbers of healthy behaviours was associated with increasing reductions in several important chronic diseases and mortality: an estimated 50% reduction in diabetes, 50% in vascular disease and 60% for all-cause mortality. These results therefore confirm previous studies and provide further data on the association of lifestyle with cognitive impairment and dementia, with a reduction of about 60% in cognitive impairment and about the same in dementia. These reductions, and especially those in cognitive function, are of enormous importance in an ageing population.

Healthy habits reduce dementia risk (Cardiff University press release):

The people who consistently followed four or five of these behaviors exp
experienced a 60 per cent decline in dementia and cognitive decline – with exercise being the strongest mitigating factor – as well as 70 per cent fewer instances of diabetes, heart disease and stroke, compared with people who followed none.
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Principle Investigator Professor Peter Elwood from Cardiff University’s School of Medicine. “What the research shows is that following a healthy lifestyle confers surprisingly large benefits to health – healthy behaviours have a far more beneficial effect than any medical treatment or preventative procedure.
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Christopher Allen, Senior Cardiac Nurse at the British Heart Foundation, which part-funded the study, said:

“The results of this study overwhelmingly support the notion that adopting a healthy lifestyle reduces your risk of cardiovascular disease and dementia.

Search for Antibiotic Solutions Continues: Killing Sleeper Bacteria Cells

Killing Sleeper Cells and Superbugs with Assassin Janitors

Discovered in 2005 by scientists from Bayer Healthcare in Germany, ADEP4 killed a variety of different bacteria and cured lethal infections in mice and rats.

Here’s how it works. Proteins need to fold into very precise shapes to do their jobs, and misfolded proteins are wastes of space. Bacteria dispose of these useless molecules with ClpP—a janitorial protein that digests other proteins. It works with a partner, which recognises misfolded proteins, unfolds them, and threads them through a hole in the middle of ClpP so they can be broken down. But ADEP4 opens ClpP up so it no longer needs its partner. The janitor now becomes an assassin, running amok and chopping up any protein it comes across, misfolded or not.

The Bayer scientists showed that ADEP4 can force fast-growing cells to self-destruct, but Lewis suspected that it would do the same to persisters. Afterall, ClpP’s partner requires energy to do its job, but ClpP itself doesn’t. Once ADEP4 opens it up, it should go about its fatal business even in a dormant cell.

Lewis’ team found that ADEP4 did effectively kills persister populations of Staphylococcus aureus, but the bacteria bounce back. ClpP isn’t essential, so the bacteria just inactivated it to evolve their way around ADEP4. This, says Lewis, is why Bayer stopped working on the drug.

His solution was to pair ADEP4 with another antibiotic called rifampycin. ADEP4 would kill off the majority of the persisters, and if any of the rest started growing again, rifampycin would finish them off. He predicted that the double-whammy would leave very few survivors, maybe just a thousand cells or so.

“That’s not what we saw,” he says. “What we saw was complete sterilisation.”

This is a very nice effort. As our efforts fail to find “magic bullet” antibiotics fail and antibiotic resistance increases combo drug solutions offer some hope. While this is good news, the overall state of our ability to treat bacterial infections continues to decline as our misuse of antibiotics has greatly increased the speed at which antibiotic resistance has developed in bacteria.

This solution only works on gram positive antibiotics. ADEP4 is too big to pass through the extra outer layers of the gram-negative bacteria like ecoli and salmonella.

Related: Entirely New Antibiotic Developed, Platensimycin (2006) (2013 update: Platensimycin is a very effective antibiotic in vivo when continuously administered to cells, however this efficacy is reduced when administered by more conventional means. Efforts continue to find a way to create delivery options that are successful in treating people.) – New Family of Antibacterial Agents Discovered (2009) – Potential Antibiotic Alternative to Treat Infection (2012)

Outdoor Air Pollution Resulted in 223,000 Cancer Deaths in 2010

The specialized cancer agency of the World Health Organization, the International Agency for Research on Cancer (IARC), announced today that it has classified outdoor air pollution as carcinogenic to humans.

After thoroughly reviewing the latest available scientific literature, the world’s leading experts convened by the IARC Monographs Programme concluded that there is sufficient evidence that exposure to outdoor air pollution causes lung cancer. They also noted a positive association with an increased risk of bladder cancer.

Particulate matter, a major component of outdoor air pollution, was evaluated separately and was also classified as carcinogenic to humans.

The IARC evaluation showed an increasing risk of lung cancer with increasing levels of exposure to particulate matter and air pollution. Although the composition of air pollution and levels of exposure can vary dramatically between locations, the conclusions of the Working Group apply to all regions of the world.

Air pollution is already known to increase risks for a wide range of diseases, such as respiratory and heart diseases. Studies indicate that in recent years exposure levels have increased significantly in some parts of the world, particularly in rapidly industrializing countries with large populations. The most recent data indicate that in 2010, 223,000 deaths from lung cancer worldwide resulted from air pollution.

“The air we breathe has become polluted with a mixture of cancer-causing substances,” says Dr Kurt Straif.

The stories of amazingly high (and persistent) air pollution levels in China have been continuing for years. But, while China, likely represents several of the worst existing air pollution conditions hundreds of thousands have died outside China due to air pollution just in the last 5 years.

Continue reading →

Deadly Trio of Acidification, Warming and Deoxygenation Threaten Our Oceans

An international panel of marine scientists is demanding urgent remedies to halt ocean degradation based on findings that the rate, speed and impacts of change in the global ocean are greater, faster and more imminent
than previously thought.

Professor Dan Laffoley, International Union for Conservation of Nature, said: “What these latest reports make absolutely clear is that deferring action will increase costs in the future and lead to even greater, perhaps irreversible, losses. The UN climate report confirmed that the ocean is bearing the brunt of human-induced changes to our planet. These findings give us more cause for alarm – but also a roadmap for action. We must use it.“

Results from the latest International Programme on the State of the Ocean (IPSO)/IUCN review of science on anthropogenic stressors on the ocean go beyond the conclusion reached last week by the UN climate change panel the IPCC that the ocean is absorbing much of the warming and unprecedented levels of carbon dioxide and warn that the cumulative impact of this with other ocean stressors is far graver than previous estimates.

Decreasing oxygen levels in the ocean caused by climate change and nitrogen runoff, combined with other chemical pollution and rampant overfishing are undermining the ability of the ocean to withstand these so-called ‘carbon perturbations’, meaning its role as Earth’s ‘buffer’ is seriously compromised.

Professor Alex Rogers of Somerville College, Oxford, and Scientific Director of IPSO said: “The health of the ocean is spiraling downwards far more rapidly than we had thought. We are seeing greater change, happening faster, and the effects are more imminent than previously anticipated. The situation should be of the gravest concern to everyone since everyone will be affected by changes in the ability of the ocean to support life on Earth.”

Among the latest assessments of factors affecting ocean health, the panel identified the following areas as of greatest cause for concern:
Continue reading →

Mechanical Gears Found in Jumping Insects

A natural example of a functioning gear mechanism has been discovered in a common insect – the plant-hopper Issus – showing that evolution developed interlocking cogs long before we did.

The gears in the Issus hind-leg bear remarkable engineering resemblance to those found on every bicycle and inside every car gear-box. Each gear tooth has a rounded corner at the point it connects to the gear strip; a feature identical to man-made gears such as bike gears – essentially a shock-absorbing mechanism to stop teeth from shearing off.

The gear teeth on the opposing hind-legs lock together like those in a car gear-box, ensuring almost complete synchronicity in leg movement – the legs always move within 30 ‘microseconds’ of each other, with one microsecond equal to a millionth of a second.

This is critical for the powerful jumps that are this insect’s primary mode of transport, as even miniscule discrepancies in synchronisation between the velocities of its legs at the point of propulsion would result in “yaw rotation” – causing the Issus to spin hopelessly out of control.

“This precise synchronisation would be impossible to achieve through a nervous system, as neural impulses would take far too long for the extraordinarily tight coordination required,” said lead author Professor Malcolm Burrows, from Cambridge’s Department of Zoology.

“By developing mechanical gears, the Issus can just send nerve signals to its muscles to produce roughly the same amount of force – then if one leg starts to propel the jump the gears will interlock, creating absolute synchronicity.

Interestingly, the mechanistic gears are only found in the insect’s juvenile – or ‘nymph’ – stages, and are lost in the final transition to adulthood. These transitions, called ‘molts’, are when animals cast off rigid skin at key points in their development in order to grow.

It may also be down to the larger size of adults and consequently their ‘trochantera’ – the insect equivalent of the femur or thigh bones. The bigger adult trochantera might allow them to can create enough friction to power the enormous leaps from leaf to leaf without the need for intermeshing gear teeth to drive it, say the scientists.

It’s not yet known why the Issus loses its hind-leg gears on reaching adulthood. The scientists point out that a problem with any gear system is that if one tooth on the gear breaks, the effectiveness of the whole mechanism is damaged. While gear-teeth breakage in nymphs could be repaired in the next molt, any damage in adulthood remains permanent. It is amazing what evolution results in, not only gears but a system that changes to a different solution (maybe, who knows the real “reason”) when the gears solution lack of robustness would create a problem for survivability.

While there are examples of apparently ornamental cogs in the animal kingdom – such as on the shell of the cog wheel turtle or the back of the wheel bug – gears with a functional role either remain elusive or have been rendered defunct by evolution.

In the video above, Professor Malcolm Burrows talks about finding the bugs that led to the science, and working with artists Elizabeth Hobbs and Emily Tracy and members of the community in the London borough of Hackney to produce the film ‘Waterfolk’.

Full press release

Another Bee Study Finds CCD is Likely Due to Combination of Factors Including Pesticides

Abstract of open access science paper funded by the United States Department of Agriculture (USDA) Crop Pollination Exposes Honey Bees to Pesticides Which Alters Their Susceptibility to the Gut Pathogen Nosema ceranae:

Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens may interact to have strong negative effects on managed honey bee colonies. Such findings are of great concern given the large numbers and high levels of pesticides found in honey bee colonies. Thus it is crucial to determine how field-relevant combinations and loads of pesticides affect bee health.

We collected pollen from bee hives in seven major crops to determine 1) what types of pesticides bees are exposed to when rented for pollination of various crops and 2) how field-relevant pesticide blends affect bees’ susceptibility to the gut parasite Nosema ceranae. Our samples represent pollen collected by foragers for use by the colony, and do not necessarily indicate foragers’ roles as pollinators. In blueberry, cranberry, cucumber, pumpkin and watermelon bees collected pollen almost exclusively from weeds and wildflowers during our sampling.

Thus more attention must be paid to how honey bees are exposed to pesticides outside of the field in which they are placed. We detected 35 different pesticides in the sampled pollen, and found high fungicide loads. The insecticides esfenvalerate and phosmet were at a concentration higher than their median lethal dose in at least one pollen sample. While fungicides are typically seen as fairly safe for honey bees, we found an increased probability of Nosema infection in bees that consumed pollen with a higher fungicide load.

Our results highlight a need for research on sub-lethal effects of fungicides and other chemicals that bees placed in an agricultural setting are exposed to.

The attempts to discover the main causes of bee colony deaths and find solutions continues to prove difficult years after the problems became major. The complex interaction of many variables makes it difficult. And special interest groups pushing pesticides and the like, which have seemed to be major contributors to the problem for years, make it even more difficult (by preventing restrictions on potentially damaging pesticide use).

The challenges in determining what is killing bees are similar to the challenges of discovering what practices are damaging human health. The success of studying complex biological interactions (to discover threats to human health) is extremely limited. I am concerned we are far too caviler about using large numbers of interventions (drugs, pesticides, massive antibiotics use in factory farms, pollution…).

Go Slow with Genetically Modified Food

My thoughts on Genetically Modified Organisms (GMO), specifically GM foods, basically boil down to:

messing with genes could create problems
we tend to (and especially those seeking to gain an advantage tend to – even if “we” overall wouldn’t the people in the position to take aggressive measures do) ignore risks until the problems are created (often huge costs at that point)
I think we should reduce risk and therefore make it hard to justify using GMO techniques
I agree occasionally we should do so, like it seems with oranges and bananas.
I agree the practice can be explained in a way that makes it seem like there is no (or nearly no) risk, I don’t trust we will always refrain from stepping into an area where there is a very bad result

Basically I would suggest being very cautious with GMO. I like science and technology but I think we often implement things poorly. I think we are not being cautious enough now, and should reduce the use of GMO to critical needs to society (patents on the practices need to be carefully studied and perhaps not permitted – the whole patent system is so broken now that it should be questioned at every turn).

Antibiotic misuse and massive overuse is an obvious example. We have doctors practicing completely unjustified misuse of antibiotics and harming society and we have factory farms massively overusing antibiotics causing society harm.

The way we casually use drugs is another example of our failure to sensibly manage risks, in my opinion. This of course is greatly pushed by those making money on getting us to use more drugs – drug companies and doctors paid by those companies. The right drugs are wonderful. But powerful drugs almost always have powerful side effects (at least in a significant number of people) and those risks are multiplied the more we take (due to interactions, weakness created by one being overwhelmed by the next etc.). We should be much more cautious but again we show evidence of failing to act cautiously which adds to my concern for using GMO.

I love antibiotics, but the way we are using them is endangering millions of lives (that is a bad thing). I don’t trust us to use science wisely and safely. We need to more consciously put barriers in place to prevent us creating massively problems.

Learn About Biology Online

Very cool site for learning about biology. I have tried the courses offered by Coursera but they are too structured for my taste. I want to be able to learn at my pace and dip into the areas I find interesting. Coursera is more like a real course, that has weekly assignments and the like.

Survivebio [site is offline, here a site you might be interested in – iBiology] is a resources that matches my desires exactly. You can go and learn about whatever topics you desire, when you desire. The site offers webcasts, games, flashcards, chapter outlines, practice tests and a forum to discuss the ideas.

In this webcast, Paul Andersen discusses the specifics of phylogenetics. The evolutionary relationships of organisms are discovered through both morphological and molecular data.

The aim of the SurviveBio web site is to aid AP (and college) biology students. But it is also a great resource to learn about biology if you are interested in that topic. Hopefully they will add more webcasts. The site uses webcasts from Bozeman Science which has a huge number of very good videos on biology and also, chemistry, physics, earth science, statistics, anatomy and physiology.

Medical Study Findings too Often Fail to Provide Us Useful Knowledge

There are big problems with medical research, as we have posted about many times in the past. A very significant part of the problem is health care research is very hard. There are all sorts of interactions that make conclusive results much more difficult than other areas.

But failures in our practices also play a big role. Just poor statistical literacy is part of the problem (especially related to things like interactions, variability, correlation that isn’t evidence of causation…). Large incentives that encourage biased research results are a huge problem.

Lies, Damned Lies, and Medical Science

He discovered that the range of errors being committed was astonishing: from what questions researchers posed, to how they set up the studies, to which patients they recruited for the studies, to which measurements they took, to how they analyzed the data, to how they presented their results, to how particular studies came to be published in medical journals. The systemic failure to do adequate long term studies once we approve drugs, practices and devices are also a big problem.

This array suggested a bigger, underlying dysfunction, and Ioannidis thought he knew what it was. “The studies were biased,” he says. “Sometimes they were overtly biased. Sometimes it was difficult to see the bias, but it was there.” Researchers headed into their studies wanting certain results—and, lo and behold, they were getting them. We think of the scientific process as being objective, rigorous, and even ruthless in separating out what is true from what we merely wish to be true, but in fact it’s easy to manipulate results, even unintentionally or unconsciously. “At every step in the process, there is room to distort results, a way to make a stronger claim or to select what is going to be concluded,” says Ioannidis. “There is an intellectual conflict of interest that pressures researchers to find whatever it is that is most likely to get them funded.”

Another problem is that medical research often doesn’t get the normal scientific inquiry check of confirmation research by other scientists.

Most journal editors don’t even claim to protect against the problems that plague these studies. University and government research overseers rarely step in to directly enforce research quality, and when they do, the science community goes ballistic over the outside interference. The ultimate protection against research error and bias is supposed to come from the way scientists constantly retest each other’s results—except they don’t. Only the most prominent findings are likely to be put to the test, because there’s likely to be publication payoff in firming up the proof, or contradicting it.

Exercise Reduces Anxiety While Also Promoting the Growth of New Neurons

Exercise reorganizes the brain to be more resilient to stress

These findings potentially resolve a discrepancy in research related to the effect of exercise on the brain — namely that exercise reduces anxiety while also promoting the growth of new neurons in the ventral hippocampus. Because these young neurons are typically more excitable than their more mature counterparts, exercise should result in more anxiety, not less. The Princeton-led researchers, however, found that exercise also strengthens the mechanisms that prevent these brain cells from firing.
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From an evolutionary standpoint, the research also shows that the brain can be extremely adaptive and tailor its own processes to an organism’s lifestyle or surroundings, Gould said. A higher likelihood of anxious behavior may have an adaptive advantage for less physically fit creatures. Anxiety often manifests itself in avoidant behavior and avoiding potentially dangerous situations would increase the likelihood of survival, particularly for those less capable of responding with a “fight or flight” reaction, she said.
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The anxiety-reducing effect of exercise was canceled out when the researchers blocked the GABA receptor that calms neuron activity in the ventral hippocampus.

Interesting research (with mice) that explores how exercise makes us more resilient to stress. I know for me, exercise seems to help relieve stress.