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Alzheimer’s and the Complex Scientific Inquiry Process

Posted on March 30, 2022  Comments (0)

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 Inquiry – Scientific Inquiry Leads to Using Fluoride for Healthy Teeth – Introduction to Fractional Factorial Designed Experiments – Benefits 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

Posted on December 30, 2021  Comments (0)

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
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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 Them – Scientific 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

Posted on May 8, 2021  Comments (1)

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.
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“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 Lie – Physical Activity for Adults: Inactivity Leads to 5.3 Million Early Deaths a Year – How Healthy Is Squid for Us? – Obesity Epidemic Explained – Kind Of

Molecular Motor Proteins

Posted on January 27, 2020  Comments (1)

Webcast on amazing processes inside cells by Ron Vale.

Molecular motor proteins are fascinating enzymes that power much of the movement performed by living organisms. The webcast provides an overview of the motors that move along cytoskeletal tracks (kinesin and dynein which move along microtubules and myosin which moves along actin). The talk first describes the broad spectrum of biological roles that kinesin, dynein and myosin play in cells. The talk then discusses how these nanoscale proteins convert energy from ATP hydrolysis into unidirectional motion and force production, and compares common principles of kinesin and myosin. The talk concludes by discussing the role of motor proteins in disease and how drugs that modulate motor protein activity can treat human disease.

Ron Vale is a Professor of Cellular and Molecular Pharmacology at the University of California, San Francisco and an Investigator of the Howard Hughes Medical Institute. He is also the founder of the iBiology project.

Related: Animations of Motor Proteins Moving Material Inside Cells – Science Explained: How Cells React to Invading Viruses – Looking Inside Living Cells

Scientists Watch Single Cell Organisms Evolve Multicellular Trait in Response to Predation

Posted on February 24, 2019  Comments (2)

The scientists used the ciliate predator Paramecium tetraurelia to select for the de novo evolution of multicellularity in outcrossed populations of C. reinhardtii. They show that multicellular life cycles that evolved were passed on to future generations (the change was heritable). The evolved multicellular life cycles are stable over thousands of asexual generations in the absence of predators. Because C. reinhardtii has no multicellular ancestors, these experiments represent a novel origin of multicellularity.

De novo origins of multicellularity in response to predation

Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations.

The control populations remained unicellular. The populations subjected to predation evolved in different ways including one that formed stereotypic eight-celled clusters (Fig. 1A), with an apparent unicellular and tetrad life stage.

electron microscope images of multicellular colonies from evolved populations

Scanning electron micrographs of representative multicellular colonies from evolved populations. (A) Shows an amorphous cluster from population B2. Cell number varies greatly between clusters in this clone and between clones in this population. (B) Shows an eight-celled cluster from population B5. Octads were frequently observed in both populations.

an external membrane is visible around both evolved multicellular colonies, indicating that they formed clonally via repeated cell division within the cluster, rather than via aggregation.

The article also provides details on the scientific inquiry process where theory meets practical realities of observation. I think these ideas are very important and we often gloss over such details. This article was shared as an open access article and is written so that those who are interested in science but are not scientists can understand, which is a valuable. The research was funded by USA National Science Foundation, the John Templeton Foundation, the NASA Astrobiology Institute, a NASA Postdoctoral Program Fellowship and a Packard Foundation Fellowship. And the researchers work at public and private universities. Such research should all be published in an open access manner.

Related: The Amazing Reality of Genes and The History of Scientific Inquiry – Parasite Evolved from Cnidarians (Jellyfish etc.) – Why Don’t All Ant Species Replace Queens in the Colony, Since Some Do – Scientific Inquiry Leads to Using Fluoride for Healthy Teeth – Mechanical Gears Found in Jumping Insects

Widespread Misuse by Those Who Use Antibiotics Infrequently Leads to Resistance

Posted on December 19, 2018  Comments (0)

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.
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“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 Aquaculture – CDC Urges Increased Effort to Reduce Drug-Resistant Infections (2006) – Antibiotics Breed Superbugs Faster Than Expected (2010)

Hope Exists to Reverse Bee Colonies Collapse if We Take Action

Posted on November 23, 2018  Comments (0)

photo of a bee on a flower

photo by Justin Hunter

The bee colony collapse disorder has been ongoing for more than 10 years and while some scientific understanding has been gained the complexity of the problem continues to stifle progress. The first post I wrote on this blog about colony collapse disorder was published in 2006.

As early as 2007 a virus was found to be one likely factor in bee colony collapse disorder. But progress has been slow especially since likely solutions were fought by those profiting from existing conditions (widespread use of powerful pesticides). In 2012, I wrote another post for this Curious Cat Science blog: Study of the Colony Collapse Disorder Continues as Bee Colonies Continue to Disappear.

Scientist unveils blueprint to save bees

Stefanie Christmann of the International Center for Agricultural Research in Dry Areas will present the results of a new study that shows substantial gains in income and biodiversity from devoting a quarter of cropland to flowering economic crops such as spices, oil seeds, medicinal and forage plants.

The UN conference is already debating new guidelines on pollinators that will recommend reducing and gradually phasing out the use of existing pesticides, but Christmann’s research suggests this can be done without financial pain or a loss of production.

The need for a change is increasingly evident. More than 80% of food crops require pollination but the populations of insects that do most of this work have collapsed. In Germany, this fall is by up to 75% over the past 25 years. Puerto Rico has seen an even sharper decline. Numbers are not available in most countries, but almost all report an alarming decline.

Related: Another Bee Study Finds CCD is Likely Due to Combination of Factors Including Pesticides (2013) – The Study of Bee Colony Collapses Continues (2007) – Europe Bans Certain Pesticides, USA Just Keeps Looking, Bees Keep Dying (2013) – Apple Farmers Use Pigs Instead of Pesticides

Animations of Motor Proteins Moving Material Inside Cells

Posted on December 23, 2017  Comments (1)

Very cool. This next video gives a bit more information on how these amazing parts of our cells move material around inside or cells.

This stuff is so interesting. I wish this type of interesting material and informative animations was what my biology education was like in k-12 instead of the boring stuff my classes were instead. I hope students today have better science classes than I did.

It is amazing how such mechanisms evolved to “walk” along transportation microtubules inside our cells.

Related: Molecular Motor Proteins webcast by Ron Vale, Professor of Cellular and Molecular Pharmacology at the University of California, San Francisco (35 minutes) – Looking Inside Living Cells – Science Explained: Cool Video of ATP Synthase, Which Provides Usable Energy to Us – Exploring Eukaryotic Cells

Cats Protect Newborns From Developing Asthma

Posted on November 11, 2017  Comments (0)

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 Cam – The History of Domestic Cats – Parasites in the Gut Help Develop a Healthy Immune System – Hypoallergenic Cats (2006) – The Amazing Reality of Genes and The History of Scientific Inquiry

Dr. Steve Goodman’s Work as a Field Biologist in Madagascar

Posted on September 2, 2017  Comments (2)

Dr. Steve Goodman‘s work is a legendary Field Biologist and spends 9-10 months out of the year conducting research in other countries, with a focus on Madagascar for nearly 30 years. Learn more about the future of Madagascar’s biodiversity and research.

This video is from the great Brain Scoop channel with Emily Graslie; if you are not following that channel I highly recommend doing so for people interested in science.

Related: The Michael Jordan of Field Biology – Insect Architecture – New Life Form Found at South African Truck Stop – Neil Degrasse Tyson: Scientifically Literate See a Different World

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

Posted on August 24, 2017  Comments (0)

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.
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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 Us – Webcasts on the Human Microbiome – People 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)