Life expectancy in the U.S. varies widely when analyzed at the census-tract level and the method may provide a more detailed picture of health disparitiesin the U.S. than other widely used analyses of life expectancy, according to new research led by Harvard T.H. Chan School of Public Health. The study is the first to analyze life expectancy data at the census-tract level across the contiguous U.S., as well as at the state and county level.
The findings were published online July 13, 2020 in Proceedings of the National Academy of Sciences (PNAS).
“Our study shows that as far as geographic variation in life expectancy is concerned, it’s a pretty local phenomenon,” said S (Subu) V Subramanian, professor of population health and geography and co-author of the study. “States are also quite important, but counties are not.”
It’s never too late to lace up some sneakers and work up a sweat for brain health, according to a study published in the May 13, 2020, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study suggests older adults, even couch potatoes, may perform better on certain thinking and memory tests after just six months of aerobic exercise.
“As we all find out eventually, we lose a bit mentally and physically as we age. But even if you start an exercise program later in life, the benefit to your brain may be immense,” said study author Marc J. Poulin, Ph.D., D.Phil., from the Cumming School of Medicine at the University of Calgary in Alberta, Canada. “Sure, aerobic exercise gets blood moving through your body. As our study found, it may also get blood moving to your brain, particularly in areas responsible for verbal fluency and executive functions. Our finding may be important, especially for older adults at risk for Alzheimer’s and other dementias and brain disease.”
Alzheimer’s disease is a progressive disorder in which the nerve cells (neurons) in a person’s brain and the connections among them degenerate slowly, causing severe memory loss, intellectual deficiencies, and deterioration in motor skills and communication. One of the main causes of Alzheimer’s is the accumulation of a protein called amyloid β (Aβ) in clusters around neurons in the brain, which hampers their activity and triggers their degeneration.
Studies in animal models have found that increasing the aggregation of Aβ in the hippocampus–the brain’s main learning and memory center–causes a decline in the signal transmission potential of the neurons therein. This degeneration affects a specific trait of the neurons, called “synaptic plasticity,” which is the ability of synapses (the site of signal exchange between neurons) to adapt to an increase or decrease in signaling activity over time. Synaptic plasticity is crucial to the development of learning and cognitive functions in the hippocampus. Thus, Aβ and its role in causing cognitive memory and deficits have been the focus of most research aimed at finding treatments for Alzheimer’s.
Genes and cardiovascular health each contribute in an additive way to a person’s risk of dementia, U.S. researchers including Sudha Seshadri, MD, and Claudia Satizabal, PhD, of The University of Texas Health Science Center at San Antonio (UT Health San Antonio) reported July 20 in the journal Neurology.
The study was conducted in 1,211 participants in the Framingham Heart Study and involved collaborators from Boston University.
Participants with a high genetic risk score based on common genetic variants, including having an allele called apolipoprotein E (APOE) ε4, were at a 2.6-fold higher risk of developing dementia than subjects who had a low risk score and did not carry the APOE ε4 allele.
Respiratory droplets from a cough or sneeze travel farther and last longer in humid, cold climates than in hot, dry ones, according to a study on droplet physics by an international team of engineers. The researchers incorporated this understanding of the impact of environmental factors on droplet spread into a new mathematical model that can be used to predict the early spread of respiratory viruses including COVID-19, and the role of respiratory droplets in that spread.
The team developed this new model to better understand the role that droplet clouds play in the spread of respiratory viruses. Their model is the first to be based on a fundamental approach taken to study chemical reactions called collision rate theory, which looks at the interaction and collision rates of a droplet cloud exhaled by an infected person with healthy people. Their work connects population-scale human interaction with their micro-scale droplet physics results on how far and fast droplets spread, and how long they last.r
Their results were published June 30 in the journal Physics of Fluids.
“The basic fundamental form of a chemical reaction is two molecules are colliding. How frequently they’re colliding will give you how fast the reaction progresses,” said Abhishek Saha, a professor of mechanical engineering at the University of California San Diego, and one of the authors of the paper. “It’s exactly the same here; how frequently healthy people are coming in contact with an infected droplet cloud can be a measure of how fast the disease can spread.”
They found that, depending on weather conditions, some respiratory droplets travel between 8 feet and 13 feet away from their source before evaporating, without even accounting for wind. This means that without masks, six feet of social distance may not be enough to keep one person’s exhalated particles from reaching someone else.
“Droplet physics are significantly dependent on weather,” said Saha. “If you’re in a colder, humid climate, droplets from a sneeze or cough are going to last longer and spread farther than if you’re in a hot dry climate, where they’ll get evaporated faster. We incorporated these parameters into our model of infection spread; they aren’t included in existing models as far as we can tell.”
The researchers hope that their more detailed model for rate of infection spread and droplet spread will help inform public health policies at a more local level, and can be used in the future to better understand the role of environmental factors in virus spread.
They found that at 35C (95F) and 40 percent relative humidity, a droplet can travel about 8 feet. However, at 5C (41F) and 80 percent humidity, a droplet can travel up to 12 feet. The team also found that droplets in the range of 14-48 microns possess higher risk as they take longer to evaporate and travel greater distances. Smaller droplets, on the other hand, evaporate within a fraction of a second, while droplets larger than 100 microns quickly settle to the ground due to weight.
This is further evidence of the importance of wearing masks, which would trap particles in this critical range.
The team of engineers from the UC San Diego Jacobs School of Engineering, University of Toronto and Indian Institute of Science are all experts in the aerodynamics and physics of droplets for applications including propulsion systems, combustion or thermal sprays. They turned their attention and expertise to droplets released when people sneeze, cough or talk when it became clear that COVID-19 is spread through these respiratory droplets. They applied existing models for chemical reactions and physics principles to droplets of a salt water solution–saliva is high in sodium chloride–which they studied in an ultrasonic levitator to determine the size, spread, and lifespan of these particles in various environmental conditions.
Many current pandemic models use fitting parameters to be able to apply the data to an entire population. The new model aims to change that.
“Our model is completely based on “first principles” by connecting physical laws that are well understood, so there is next to no fitting involved,” said Swetaprovo Chaudhuri, professor at University of Toronto and a co-author. “Of course, we make idealized assumptions, and there are variabilities in some parameters, but as we improve each of the submodels with specific experiments and including the present best practices in epidemiology, maybe a first principles pandemic model with high predictive capability could be possible.”
There are limitations to this new model, but the team is already working to increase the model’s versatility.
“Our next step is to relax a few simplifications and to generalize the model by including different modes of transmission,” said Saptarshi Basu, professor at the Indian Institute of Science and a co-author. “A set of experiments are also underway to investigate the respiratory droplets that settle on commonly touched surfaces.”
In the nearly a week since I posted A Beginner’s Guide to Earthing – Part One I have learned some new things about Earthing that I wanted to pass on to you. Also, Paul, the blogger who wrote the original post that got me interested in Earthing sent in a most useful comment that I am reproducing here as it is loaded with good resources.
The website GoingBarefoot.org has much information, including real-life experiences from customers. That website suggests it is the work of Martin Zucker, one of the authors of the book. It also offers a testimonial video. All found by going here: http://www.goingbarefoot.org
One of the items in the earthing sheet kit was a 74-minute, professionally-made film that was fascinating. Guess what! That film is available as a YouTube video. Link here: https://www.youtube.com/watch?v=jgwF0tpioTU
In writing most of the nearly 4000 posts in this blog, I have always felt a reasonable confidence and certainty about my grasp of the subject. I don’t know who said it first, but this time it’s different. I am the beginner. Before late June I don’t believe I had ever even heard of Earthing or its other name Grounding. I stumbled across it in one of the blogs I read – Learning From Dogs.
As a dog lover this title naturally attracted me. There turns out to be a great deal more to the posts than simple dog info. In late June I ran across this post – all about Earthing.
I confess the term ‘Earthing’ was new to me. As you can read in his post, however, the practice seemed to hold very high promise as far as being a healthy practice. Since sleeping on an…
Higher consumption of fruit, vegetables and whole grain foods are associated with a lower risk of developing type 2 diabetes, according to two studies published by The BMJ.
The findings suggest that even a modest increase in consumption of these foods as part of a healthy diet could help prevent type 2 diabetes.
In the first study, a team of European researchers examined the association between blood levels of vitamin C and carotenoids (pigments found in colourful fruits and vegetables) with risk of developing type 2 diabetes.
You’ve probably heard the expression, “you are what you eat,” but what exactly does that mean? Put simply, food is fuel, and the kinds of foods and drinks you consume determine the types of nutrients in your system and impact how well your mind and body are able to function according to Mental Health America.
Avoid: Sugary drinks and excessive amounts of caffeine. Sugary drinks have empty calories and damage tooth enamel. Caffeine should also be avoided in excess, as it can trigger panic attacks in people who have anxiety disorders.
Try to: Drink at least 8 glasses of water a day (about 2 liters) to prevent dehydration. Studies show that even mild dehydration can cause fatigue, difficulty concentrating, and mood changes1, in addition to physical effects like thirst, decreased or dark urine, dry skin, headache, dizziness and/or constipation. Limit caffeine if you have an anxiety disorder. If you feel like you need some caffeine, try tea. Tea has lower amounts of caffeine than coffee and has lots of antioxidants-chemicals found in plants that protect body tissues and prevent cell damage.
Early infections of influenza A can help predict how the virus will affect people across different ages in the future and could impact the effectiveness of flu vaccines, says a new study published in eLife.
The findings may help improve estimates of both the age-specific risk of acquiring seasonal influenza infections and vaccine effectiveness in similarly vaccinated populations.
Seasonal influenza is an acute respiratory infection caused by influenza viruses that occur across the world. It causes approximately 100,000–600,000 hospitalisations and 5,000–27,000 deaths per year in the US alone. There are three types of seasonal influenza viruses in humans: A, B and C, although C is much less common. Influenza A viruses are further classified into subtypes, with the A(H1N1) and A(H3N2) subtypes currently circulating in humans. A(H1N1) is also written as A(H1N1)pdm09 as it caused the 2009 pandemic and replaced the A(H1N1) virus which had circulated before that year.
With more than 30 million Americans diagnosed with diabetes, and another 87 million diagnosed with obesity, both conditions have become national epidemics.
The two diseases cause a number of complications, including neuropathy, which causes damage to the peripheral nerves. Neuropathy is characterized by numbness or tingling and can sometimes be accompanied by pain.
A little-studied liver protein may be responsible for the well-known benefits of exercise on the aging brain, according to a new study in mice by scientists in the UC San Francisco Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research. The findings could lead to new therapies to confer the neuroprotective effects of physical activity on people who are unable to exercise due to physical limitations.
Exercise is one of the best-studied and most powerful ways of protecting the brain from age-related cognitive decline and has been shown to improve cognition in individuals at risk of neurodegenerative disease such as Alzheimer’s disease and frontotemporal dementia — even those with rare gene variants that inevitably lead to dementia.
I was a fish eating vegetarian for some years. Had no trouble maintaining my weight, but often longed for a burger. While I eat meat now, it is only rarely.
Experts agree plants should make up a large part of a healthy dietary pattern. Humans eat plant roots (carrots and radishes), stems (asparagus and celery), leaves (leafy greens), seeds (including whole grains), flowers (broccoli, cauliflower, artichoke), and the seed-bearing “fruits” of plants (including fruits, vegetables, beans, and nuts). All are packed with important health-promoting nutrients, and countless studies have found associations between consuming diets higher in unprocessed plant foods and lower risk for a wide range of disorders such as cardiovascular disease, cancer, obesity, and diabetes.
But recommendations to eat a “plant-based” diet can be misleading. “I really dislike the term plant-based to describe a preferred or healthy diet,” says Dariush Mozaffarian, MD, DrPH, dean of Tufts’ Friedman School of Nutrition Science and Policy and editor-in-chief of Tufts Health & Nutrition Letter. “Not all animal-based foods are bad, and most of the worst things in the food supply are technically plant-based.” A vegetarian diet built on pizza, macaroni-and-cheese, and baked goods may be “plant-based,” but it’s far from a healthy dietary pattern.
A growing body of research suggests heart attacks, angina and other heart events increase during winter and summer.
Now, a new study could explain why.
Researchers reviewed an international registry of 1,113 people, the majority from Japan, with acute coronary syndrome. Heart attack is a type of acute coronary syndrome, which occurs when the blood supply to the heart muscle is suddenly decreased or blocked.
Using images of the fatty deposits in participants’ coronary arteries, researchers put people into groups: plaque rupture, plaque erosion and calcified plaque. Each plaque scenario can block blood flow and lead to a heart attack or other cardiac event. But a rupture is more immediate and occurs when the calcified plaque breaks off. Erosion can happen over time.
“We looked at those three underlying mechanisms to see whether they were different among the different seasons. As expected, we found a significant difference,” said Dr. Ik-Kyung Jang, lead author of the study published Thursday in the Journal of the American Heart Association. Jang is an interventional cardiologist and director of the Cardiology Laboratory of Integrated Physiology and Imaging at Massachusetts General Hospital in Boston.