Posts about human health

Alzheimer’s and the Complex Scientific Inquiry Process

This webcast provides an interesting look at the complex scientific inquiry process: An Alzheimer’s Drug That Doesn’t Treat Alzheimer’s?

Medical research is complex. Once we figure out what is most critical and discover effective treatments often the explanations can then make it seem fairly simple. But that process is often decades of efforts that include years of frustration and confusion.

For long term medical impacts we often need to guess at important biomarker indications that may be closely related to health outcomes. But that process often isn’t as easy as it sounds.

Much Alzheimer’s research for the last few decades has focused on amyloid plaque reduction.

A new Alzheimer’s drug has been approved. But should you take it?

Aducanumab (brand name Aduhelm) is a monoclonal antibody engineered in a laboratory to stick to the amyloid molecule that forms plaques in the brains of people with Alzheimer’s. Most researchers believe that the plaques form first and damage brain cells, causing tau tangles to form inside them, killing the cells. Once aducanumab has stuck to the plaque, your body’s immune system will come in and remove the plaque, thinking it’s a foreign invader. The hope and expectation are that, once the plaques are removed, the brain cells will stop dying, and thinking, memory, function, and behavior will stop deteriorating.

I personally do not think the drug should have been approved. Continued research would be fine, but approving an extraordinarily expensive drug without strong evidence of significant positive health outcomes is very poor public policy.

Related: The Amazing Reality of Genes and The History of Scientific InquiryScientific Inquiry Leads to Using Fluoride for Healthy TeethIntroduction to Fractional Factorial Designed ExperimentsBenefits of a Mediterranean Diet May Include Reduced Risk of Cognitive Impairment As We Age

mRNA Vaccine Targets Ticks to Allow Us to Avoid Diseases Ticks Carry

A lab-stage mRNA vaccine targeting ticks may offer protection against Lyme and other tick-borne diseases

A new laboratory-stage mRNA vaccine that teaches the immune system to recognize the saliva from tick bites could prevent these bugs from feeding on and transmitting tick-borne diseases to people

What’s unique about the 19ISP mRNA vaccine is that instead of directly targeting the pathogen that causes the disease like traditional vaccines, 19ISP was able to stimulate resistance to the carrier of the disease, ticks, and prevent them from transmitting the pathogen in the first place. Our study also suggests that this form of tick-based vaccination – teaching the body to rapidly recognize and react to being bitten by a tick – may be sufficient to prevent infection.

mRNA vaccines have been in the news a great deal due to the covid19 mRNA vaccines. The potential for mRNA solutions is very promising. If this research can be confirmed and brought to market it could save us from Lyme disease and other diseases transmitted via ticks.

Related: New and Old Ways to Make Flu Vaccines (2007)Vaccines Can’t Provide Miraculous Results if We Don’t Take ThemScientific Illiteracy Leads to Failure to Vaccinate Which Leads to Death (2012)US Fish and Wildlife Service Plans to Use Drones to Drop Vaccine Treats to Save Ferrets

Benefits of a Mediterranean Diet May Include Reduced Risk of Cognitive Impairment As We Age

Medical studies about healthy living are very complex and not easy to draw clear conclusions from. But the evidence continues to grow on the benefits of a healthy Mediterranean diet.

Mediterranean diet may prevent memory loss and dementia, study finds

The true diet is simple, plant-based cooking, with the majority of each meal focused on fruits and vegetables, whole grains, beans and seeds, with a few nuts and a heavy emphasis on extra-virgin olive oil. Fats other than olive oil, such as butter, are consumed rarely, if at all. And say goodbye to refined sugar or flour.

Meat can make a rare appearance, but usually only to flavor a dish. Instead, meals may include eggs, dairy and poultry, but in much smaller portions than in the traditional Western diet. However, fish, which are full of brain-boosting omega-3’s, are a staple.

“Eating a healthy plant-based diet is associated with better cognitive function and around 30% to 35% lower risk of cognitive impairment during aging,” lead author Claire McEvoy, assistant professor at Queen’s University Belfast

I am skeptical of the size of the risk reduction. It is seems decades of health studies show that precise measures are not that trustworthy. But it does seem that there are many benefits to a Mediterranean diet.

photo of fish dish

This is actually a photo of a dinner I enjoyed while in Malaysia (which just is one I had easy access to add to this post)

I have been taking this into account in my eating. I try to eat much more green leafy vegetable (though more is from my very low levels before). I try to reduce the amount of meat and increase the amount of fish and nuts. I try to eat enough fiber and I eat yogurt. I try to eat more fruits and vegetables in general. I try to reduce the amount of processed foods and sugar. My diet is far from great but it is much better than is was 20 years ago. I have probably been focused on doing better for over 10 years (post from 9 years ago: Healthy Diet, Healthy Living, Healthy Weight).

Related: Eat food. Not too much. Mostly plants.Big Fat LiePhysical Activity for Adults: Inactivity Leads to 5.3 Million Early Deaths a YearHow Healthy Is Squid for Us?Obesity Epidemic Explained – Kind Of

Appropriate Technology: a Microscope and Centrifuge for Under $1

Malaria is estimated to have killed more than half the people that have ever lived. And it continues to kill millions. One big challenge is diagnosing malaria is difficult (those infected have flu like symptoms).

The video shows two great appropriate technology solutions to help diagnose malaria and save millions of lives. Manu Prakash from Stanford talks about 2 of his labs’ inventions the Foldscope and the Paperfuge. Combined these cost only 68 cents and they can be used to diagnose Malaria. Both of these are examples not only of simple, brilliant design, but of how engineering is used to make a positive dent in the world.

Read more about the Paperfuge: an ultra-low cost, hand-powered centrifuge inspired by the mechanics of a whirligig toy (open access paper).

This solution also shows the huge benefit people everywhere have gained when immigrants can take their skills and desires to institutions like Stanford to create solutions that greatly benefit the world. This powerful force has been creating huge benefits that we all have enjoyed for decades.

Related: Appropriate Technology and Focus on Improving Lives at MIT (2014)$1 Device To Give Throat Cancer Patients Their Voice Again (2016)Video showing malaria breaking into cell (2011)Engineering: Cellphone Microscope (2009)One Scientists 20 Year Effort to Defeat Dengue Fever (2012)

Widespread Misuse by Those Who Use Antibiotics Infrequently Leads to Resistance

Widespread, occasional use of antibiotics in USA linked with resistance

The increasing prevalence of antibiotic resistance in the U.S. appears more closely linked with their occasional use by many people than by their repeated use among smaller numbers of people, according to a large new study from Harvard T.H. Chan School of Public Health.

The study also found that antibiotic use varies across the nation, and that in areas where particular antibiotics are used more frequently, resistance to those antibiotics is higher.

“We know that efforts to reduce inappropriate use of antibiotics are critical to addressing the problem of antibiotic resistance.

“Our results show that most antibiotic use is occasional—by people taking just one antibiotic course in a year—and that this occasional use is more closely linked with antibiotic resistance than intense, repeated use.”

The problems created by misuse of antibiotics are significant and continuing. The consequences are long term and diffuse. The lack of immediate and damaging impacts makes the continued misuse seem to have little consequence. However, the consequences are dire but not immediate.

In this way it is similar to the problems caused by pumping huge amounts of green house gases into the atmosphere and causing massive climate changes (though delayed by several decades). As a society we really have to get better at changing our behavior when the long term consequences are dire and clear.

It is good to learn from these efforts to understand the most significant aspects of our continued misuse of antibiotics in order to prioritize where we focus our improvement efforts.

Related: What Happens If the Overuse of Antibiotics Leads to Them No Longer Working? (2011)Our Dangerous Antibiotic Practices Carry Great Risks (2012)80% of the Antibiotics in the USA are Used in Agriculture and AquacultureCDC Urges Increased Effort to Reduce Drug-Resistant Infections (2006)Antibiotics Breed Superbugs Faster Than Expected (2010)

Cats Protect Newborns From Developing Asthma

Everyone should appreciate the value of cats (as we do, honoring cats in our blog’s name); yet some people seem oblivious to the greatness of cats. In another demonstration of what we gain by associating with cats, research has shown living with cats as newborns helps protect those with a specific gene variation from developing asthma.

Cats protect newborns against asthma

The results reveal that cats remove the increased risk of developing asthma among children with a particular variation of the gene 17q21, called TT, which has the strongest impact on whether or not a child could develop asthma.

Almost one in three children in the study carried the TT gene variant, regardless of whether or not their mother had asthma.

“it looks like the effect is linked to a particular gene-variant, which goes to show just how complex the development of asthma and allergies are. It’s not only about genes and the environment, but how the two interact, and there’s so much that we still don’t know,”

The research indicates that cats reduce the risk of childhood asthma, pneumonia, and bronchiolitis in genetically susceptible subjects.

And no, dogs do not provide this protection. As with most research the scientists have new paths of inquiry to follow based on these results. Lead author Jakob Stokholm suspects that the reasons cats have this effect but dogs do not, “could be related to the bacteria that cats carry and perhaps fungi or viruses that they bring into the home”. Those questions can be the topic of further research.

Related: Cat Allergy Vaccine Created (2011)Awesome Cat CamThe History of Domestic CatsParasites in the Gut Help Develop a Healthy Immune SystemHypoallergenic Cats (2006)The Amazing Reality of Genes and The History of Scientific Inquiry

Stanford Research Scientists Discover 99% of the Microbes Inside Us are Unknown to Science

Readers of this blog know I am fascinated by the human microbiome. It is amazing how much of our biology is determined by entities within us that are not us (at least not our DNA) (bacteria, viruses etc.). This whole area of study is very new and we have quite a bit to learn. There are scientists across the globe studying this area and learning a great deal.

Stanford study indicates that more than 99% of the microbes inside us are unknown to science

Of all the non-human DNA fragments the team gathered, 99 percent of them failed to match anything in existing genetic databases the researchers examined.

The “vast majority” of it belonged to a phylum called proteobacteria, which includes, among many other species, pathogens such as E. coli and Salmonella. Previously unidentified viruses in the torque teno family, generally not associated with disease but often found in immunocompromised patients, made up the largest group of viruses.

“We’ve doubled the number of known viruses in that family through this work,” Quake said. Perhaps more important, they’ve found an entirely new group of torque teno viruses. Among the known torque teno viruses, one group infects humans and another infects animals, but many of the ones the researchers found didn’t fit in either group. “We’ve now found a whole new class of human-infecting ones that are closer to the animal class than to the previously known human ones, so quite divergent on the evolutionary scale,” he said.

Related: We are Not Us Without The Microbes Within UsWebcasts on the Human MicrobiomePeople are Superorganisms With Microbiomes of Thousands of Species (2013)We Have Thousands of Viruses In Us All the Time (2015)Tracking the Ecosystem Within Us (2007)

Drone Deliveries to Hospitals in Rwanda

Partnering with the Government of Rwanda, Zipline serves 21 hospitals nation-wide. They provide instant deliveries of lifesaving blood products for 8 million Rwandans.

Their drones are tiny airplanes (instead of the more common tiny helicopter model). Supplies are delivered using parachute drops from the drone. Landings are similar to landings on aircraft carriers (they grab a line to help slow down the drone) and, in a difference from aircraft carrier landings, the drone line drops them onto a large air cushion.

Zipline Muhanga Distribution Center launched in October 2016 making Rwanda the first country to integrate drones into their airspace and to begin daily operations of autonomous delivery.

As of May 2017, Zipline had completed over 350 delivery flights to real hospitals and their pace is accelerating. Zipline can cut delivery time from 4 hours to 15 minutes (which is extremely important in time critical health care emergencies).

I wrote in 2014 about the huge potential for drone delivery of medical supplies. It is wonderful to see Zipline improving people’s lives with their effort.

Related: Inspirational Engineer, William Kamkwamba from Malawi (2008)Using Rats to Sniff Out TBUS Fish and Wildlife Service Plans to Use Drones to Drop Vaccine Treats to Save FerretsWater Wheel

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We are Not Us Without The Microbes Within Us

I Contain Multitudes is a wonderful book by Ed Young on the microbes within us.

Time and again, bacteria and other microbes have allowed animals to transcend their basic animalness and wheedle their way into ecological nooks and crannies that would be otherwise inaccessible; to settle into lifestyles that would be otherwise intolerable; to eat what they could not otherwise stomach; to succeed against their fundamental nature. And the most extreme examples of this mutual assured success can be found in the deep oceans, where some microbes supplement their hosts to such a degree that the animals can eat the most impoverished diets of all – nothing.

This is another book exploring the wonders of biology and the complexity of the interaction between animals and microbes.

For hundreds of years, doctors have used dioxin to treat people whose hearts are failing. The drug – a modified version of a chemical from foxglove plants – makes the heart beat more strongly, slowly, and regularly. Or, at least, that’s what it usually does. In one patient out of every ten, digoxin doesnt’ work. Its downfall is a gut bacterium called Eggerthella lenta, which converts the drug to an inactive and medically useless form. Only some strains of E. lenta do this.

The complex interactions within us are constantly at work helping us and occasionally causing problems. This obviously creates enormous challenges in health care and research on human health. See related posts: Introduction to Fractional Factorial Designed Experiments, “Grapefruit Juice Bugs” – A New Term for a Surprisingly Common Type of Surprising Bugs and 200,000 People Die Every Year in Europe from Adverse Drug Effects – How Can We Improve?.

Every person aerosolized around 37 million bacteria per hour. This means that our microbiome isn’t confined to our bodies. It perpetually reaches out into our environment.

Avoiding bacteria is not feasible. Our bodies have evolved with this constant interaction with bacteria for millions of years. When we are healthy bacteria have footholds that make it difficult for other bacteria to gain a foothold (as does our immune system fighting off those bacteria it doesn’t recognize or that it recognized as something to fight).

A few pages later he discusses the problem of hospital rooms that were constantly cleaned to kill bacteria and largely sealed to reduce airflow. What happened is those bacteria the sick people had in them were the bacteria that were flourishing (the number of other bacteria to compete for space was small). Opening the windows to welcome the outside air resulted in better results.

Outdoors, the air was full of harmless microbes from plants and soils. Indoors, it contained a disproportionate number of potential pathogens, which are normally rare or absent in the outside world

Human health is a fascinating topic. It is true antibiotics have provided us great tools in the service of human health. But we have resorted to that “hammer” far too often. And the consequences of doing so is not understood. We need those scientists exploring the complex interactions we contain to continue their great work.

Related: People are Superorganisms With Microbiomes of Thousands of Species (2013)Bacteria are Always Living in Our Bodies (2014)Gut Bacteria Explored as Medical Treatment – even for Cancer

Unexpected Risks Found In Editing Genes To Prevent Inherited Disorders

Mitochondrial replacement seeks to remove genes known to cause genetic defects from embryos in order to allow for a baby to avoid inheriting the defect.

Mitochondrial Replacement Techniques: Ethical, Social, and Policy Considerations from the USA National Academy of Sciences

Accordingly, the committee recommends that any initial MRT clinical investigations focus on minimizing the future child’s exposure to risk while ascertaining the safety and efficacy of the techniques. The recommended restrictions and conditions for initial clinical investigations include

  • limiting clinical investigations to women who are otherwise at risk of transmitting a serious mtDNA disease, where the mutation’s pathogenicity is undisputed, and the clinical presentation of the disease is predicted to be severe, as characterized by early mortality or substantial impairment of basic function; and
  • transferring only male embryos for gestation to avoid introducing heritable genetic modification during initial clinical investigations.

Following successful initial investigations of MRT in males, the committee recommends that FDA could consider extending MRT research to include the transfer of female embryos if clear evidence of safety and efficacy from male cohorts, using identical MRT procedures, were available, regardless of how long it took to collect this evidence; preclinical research in animals had shown evidence of intergenerational safety and efficacy; and FDA’s decisions were consistent with the outcomes of public and scientific deliberations to establish a shared framework concerning the acceptability of and moral limits on heritable genetic modification.

The research in this area is interesting and our ability to help achieve healthy lives continues to grow. The path to a bright future though is not without risk. It requires careful action to pursue breakthrough improvements while minimizing the risks we take to achieve better lives for us all.

Unexpected Risks Found In Editing Genes To Prevent Inherited Disorders

Earlier this month, a study published in Nature by Shoukhrat Mitalipov, head of the Center for Embryonic Cell and Gene Therapy at the Oregon Health and Science University in Portland, suggested that in roughly 15 percent of cases, the mitochondrial replacement could fail and allow fatal defects to return, or even increase a child’s vulnerability to new ailments.

The findings confirmed the suspicions of many researchers, and the conclusions drawn by Mitalipov and his team were unequivocal: The potential for conflicts between transplanted and original mitochondrial genomes is real, and more sophisticated matching of donor and recipient eggs — pairing mothers whose mitochondria share genetic similarities, for example — is needed to avoid potential tragedies.

“This study shows the potential as well as the risks of gene therapy in the germline,” Mitalipov says. This is especially true of mitochondria, because its genomes are so different than the genomes in the nucleus of cells. Slight variations between mitochondrial genomes, he adds, “turn out to matter a great deal.”

Related: Gene Duplication and EvolutionThe Challenge of Protecting Us from Evolving Bacterial ThreatsOne Species’ Genome Discovered Inside Another’s (2007)Looking Inside Living Cells

Engineering Mosquitos to Prevent the Transmission of Diseases

Mosquitos are responsible for huge amount of suffering and death. In 2015 200,000,000 people were infected with malaria and 500,000 died.

It is amazing what knowledge science has provided about the causes of human disease. It is great to have videos like this available that let us learn a bit about it from a short and understandable video.

Using our scientific knowledge to design and implement solutions offers great possibilities. But we also have to worry about the risks of such attempts. Making decisions about what risks to take requires well informed people that are able to understand the opportunities and risks and make intelligent decisions.

Related: Video showing malaria breaking into cellScientists Building a Safer Mosquito (2006)Engineering Mosquitoes to be Flying Vaccinators (2010)