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Air’s journey in quick-growing cities

Text and pictures by Kabisha Velauthapillai

Have you ever thought about the journey our air takes to eventually reach the depths of our lungs? From our lungs, the air goes on a fluid adventure through our blood, reaching our brain, our heart, and the tips of our toes. What about our air’s journey before we breathe it in? Where does it come from? A lot of research on environment and health is focused on this exactly: the journey of air pre-breath and the journey post-breath. We’re finding out just how complicated the air around us is. Our air is made of tiny particles. Some particles keep us healthy, while others contribute to bad health like heart and lung disease.

With air being everywhere, all around us, all the time, air pollution is hard to get away from. Air pollutants come from very different places. For instance, what’s the first thing you thought of when you read the words “air pollution”. For a lot of people, the first image they think of is the distant factory with a thick greyish smoke rising from it. Pollution from factories can seem hard to stop, but there’s another, more common, more immediate place that might be a bit easier for us to act on as average citizens. This ‘place’ is TRAFFIC.

Traffic on highway study city

A main highway passing from the North to the South of the city.

That’s right, the collective of vehicles we drive throughout the day, week, month, year all add up. Traffic ends up being a major source of air pollution in cities around the world. It’s especially a problem in cities growing at a very quick pace. The quick growth often means we don’t have enough time to plan for a city structure and city services that can accommodate a growing number of people. With more people, streets are more crowded and more vehicles are zooming, sometimes zig-zagging, from one place to another. In the Global South many are moving from rural areas to cities, searching for stable opportunities for their families and themselves. That’s why quick-growing cities with increasing traffic are particularly common in the Global South.

Research on traffic-related air pollution is abundant in the Global North, where there are more resources put toward these studies, but the research is greatly lacking in the Global South. You may be asking: “well, what’s wrong with applying traffic research from the Global North to cities in the Global South?” That’s a great question. The thing is, cities in the North have typically been around for much longer, meaning more preparation for growth. They also typically experience different environments compared to cities in the South. Remember when we were talking about the journey of air at the beginning? We’re bringing that right back here. The types and amounts of harmful tiny air particles can be different in Global South and Global North cities. They are often different between Global South cities too, because of climate types, altitude, types of economies, and a lot more. This is why it’s important to study the journey of air in different cities, especially when the information is not there.

Women walking in an alley

An alley in El Alto Viento: one of the study neighbourhoods.

Traffic-related air pollution in the Global South is a public health dilemma, calling policy makers and urban planners to the table. However, to get these stakeholders involved, we need well thought-out, properly designed research in epidemiology, which studies the health of populations. We need to research the types and amounts of harmful air pollutants and how they can affect people’s health. This was the goal of a pilot study conducted by the Baumgartner research group this summer. The interdisciplinary, multi-country team collected data in Bucaramanga, Colombia. Right now, we are analyzing the data, trying to better understand how air pollution might affect the health of people in Bucaramanga.

Scientific equipment

An outdoor roof kit set-up.

By figuring out the types and amounts of harmful tiny air particles and their impacts on health, we can better understand how the air we breathe can also negatively affect us. Many of us have families and roots in the Global South, making it all that much important to study the impacts of air pollutants on the health of people. It’s essential that such research takes place through South-North collaborations, supporting people who are already engaged in cities in the Global South. Maintaining a culture of solidarity with our partners in the South is key for working toward improved health of the global population.

In addition to these studies, it’s important to get the word out about traffic-related air pollution: what it is, how it affects our health, what people are doing about it, and what we CAN do about it. Each one of us have the right to know and to engage in this discussion on an issue that affects us all.

More about the author here.

Having a disability in Africa – What’s that like?

Written by Shaun Cleaver

Those people must be the poorest of the poor!

Just to stay alive in those circumstances – such resilience!

I work with people with disabilities in Zambia, a country in southern Africa that North Americans seem to vaguely recognize. When I am in Canada and talking about my work, I often hear comments like the ones above – where Canadian presume that Zambians with disabilities live in either hopelessness or infinite inner strength.

From my interactions, this not a case of “either/or” – especially not the extremes of “either/or” that people imagine.

The imaginations of Canadians are probably informed by what they can remember about Zambia – which is generally very little. Much more is known about Africa! For example:

  1. There are animals there.
  2. There is lots of poverty.
  3. Corruption is a problem.
  4. There are wars, right? I thought I heard there was a war or something.

The thing is, many of those points are at least partly true for countries within the continent of Africa. Africa is big. There is lots of diversity. And yet there are commonalities that are true in many places much of the time.

In the case of Zambia, there are lots of amazing animals, there is terrible poverty and corruption is a problem. Yet Zambia is also quite peaceful. In addition, the country has been experiencing steady economic growth for years and is having an explosion of shopping malls in the capital. Somehow, Canadians never seem to spontaneously imagine those last two points.

Of the stereotypes applied to Africa more generally, these are often true, but not all of them, not everywhere, and not all of the time. More importantly, the stereotype list is incomplete.

How did I get to slagging stereotypes when this post was supposed to be about disability?

The reason is that Canadians seem to apply a parallel version of the stereotypes of Africa to their impressions of the individuals with whom I work.

So what is life like for them?

Before I get into some details, this seems like a good time to review the balance between extrapolation (and stereotypes when this really goes rampant) and specificity. In my work, I have spoken with a few hundred Zambians with disabilities. Each and every one of them has a rich biography, that could fill pages. Just like you or I. That is the thing with being a human – Zambian, Canadian, other nationality; disabled, not-currently-disabled, sort-of-disabled, etc. We all share this in common. At the same time, there are commonalities, writ large, that apply to the current realities of Zambia.

With all of the above in-mind, let me tell you two things that are specific to the experience of disability in Zambia today. Both of these things have to do with socio-economics.

As mentioned above, Zambia is a poor country, and I can confirm that my research people with disabilities speak a lot about their poverty. Like constantly. But I also mentioned Zambia’s economic growth – growth that is creating new formal employment opportunities for Zambians. And yet, these opportunities are not distributed equally. The multinational stores within those previously-mentioned shopping malls are actually good at hiring persons with disabilities when they apply. Except, how do you make it to work when there is no accessible transportation? How do you present yourself as qualified when the stores have their pick of university graduates? Meanwhile, you were sent home from high school because, “spaces are limited and none of those spaces are for students like you.” Zambia’s economic growth brings opportunities, but there are signs that the inequality of those opportunities is increases the income gap between persons with and without disabilities, rather than reducing it.

The second thing I will tell you is that Zambia is building a public social safety net. These days, we in Canada experience an erosion in public services while some people shout, “government is too big!” Meanwhile, Zambians know very well that not having government services is a very big problem. With the economy growing on the whole, the Government of Zambia is investing in targeted ways to address severe poverty, and persons with disabilities are among the target groups.

Given the shifting present realities, what should be the socio-economic future of disability? Should Zambians with disabilities look forward to major shifts in society so that they are no longer discriminated from opportunities as they arise? Or should they foresee that social welfare programs will financially compensate them for society’s cumulative discrimination?

When I ask this question to the people with disabilities who I work with, this is how they answer:

Yes, we should get out of poverty. So Shaun, what are you going to do to help make this happen?

More about the author:
@ShaunCleaver is a global health postdoctoral fellow in SPOT, at McGill.
He blogs on his research with Zambians with disabilities at
www.disability-kwa-bulozi.com

Can a cellular traffic jam ‘jam up’ learning?

Image Credit: China Daily/Reuters

By Andy Gao

Having a child is a joyous event for most families, but what if your precious bundle of joy didn’t develop like all of the other children? Imagine scrolling anxiously through parenting books and wondering why your baby isn’t developing the ability to walk and talk normally; why they don’t look like your friends’ babies; and why they might even start convulsing and seizing. Imagine bringing your child to your pediatrician, who conducts a number of examinations but ultimately cannot determine what exactly is wrong with them or how to treat them. What would you do?

This scenario might be hard to fathom, but unfortunately, these are the types of complications that a number of families must face when raising a child with a rare disorder. True to their name, each rare disorder affects only a small number of people, but taken together, they afflict a much more significant proportion of the population worldwide. In fact, since both primary caretakers and the general public may simply be unaware of these disorders, they can often go unnoticed and rates of these diseases may be highly underestimated.

Even so, what if some of the basic cellular deficits underlying some of these disorders could be common to much broader range of more common diseases that people are actually familiar with, such as Alzheimer’s and Parkinson’s? Now, researchers may have discovered one such possible mechanism worthy of further investigation.

Like cities, neurons (brain cells) also need to traffic cargo around them in order to function properly. In order to do this, most cells use small circular structures called endosomes to transport different proteins inside of them. The internal acidity, or pH, of these endosomes is essential for their proper function and is regulated by transporters that pump in or remove hydrogen ions (protons) from these structures. One of these transporters, dubbed NHE6 (or sodium/proton exchanger 6, and if you’re wondering where the N and H come from, look back at your periodic table abbreviations), has gained particular interest in recent years. In particular, the gene encoding NHE6 is found to be mutated in some rare developmental disorders whose symptoms include intellectual disability, movement disorders, severe seizures, autistic behaviour, and more. As NHE6 is involved in cell trafficking, if it isn’t functioning properly, it could result in a cellular “traffic jam” of sorts that could go on to disrupt the function of the entire cell as well. The question then becomes how this cellular “traffic jam” could impair brain function to cause these devastating symptoms.

For a long time, it was known that NHE6 is present in other bodily tissues, including the brain, heart, and muscles, but its role in neural function remained elusive. Recently, our lab characterized the presence of NHE6 in the hippocampus, a brain structure involved in learning and memory. In the neurons of the hippocampus, we found that NHE6 was present specifically at synapses, the points of contact between brain cells that allow them to communicate with one another. Interestingly enough, when we induced a cellular learning model on these hippocampal cells, which usually results in the strengthening of these synapses, we found that more NHE6 was localized to these synapses. These experiments told us that NHE6 was indeed involved in learning and memory in the brain.

We then moved on to address the question of how removing the function of NHE6 could result in the severe neurological deficits that have been observed in rare disorders. To address this, we grew hippocampal neurons in a dish and made them express mutant versions of the NHE6 protein. We found that compared to normal cells, these neurons looked “sick” and didn’t form as many synapses with one another. In addition, they were also less able to transport certain proteins using their endosomes. Interestingly enough, when we induced a cellular learning paradigm, these cells failed to strengthen their synapses like normal cells did. This finding was important, as it could be the underlying mechanism behind cognitive impairment in patients with rare mutations in the NHE6 gene as well as those with more common neurodegenerative diseases, including Alzheimer’s and Parkinson’s. Genome studies in these latter groups of patients have actually uncovered a decrease in the amount of NHE6 in their brains. As a result, this could prevent their brain cells from functioning properly and lead to the distinctive impairments associated with these devastating diseases.

In summary, recent findings have indicated that changes in the functionality of something like NHE6 can indeed impair the ability of brain cells to communicate with one another and, more importantly, strengthen these connections in response to cellular activity. This could, in turn, prevent patients with changes in NHE6 function to learn things about the world around them and form new memories. We hope that by discovering the underlying cause behind such disorders, no matter how rare or common, we can begin to develop new therapeutic measures to manipulate these transporters and reverse the neuronal impairments brought about by cellular mistrafficking.

And even if such therapies are still a long way in the making, at least the families and caretakers of children with these rare disorders know that someone, somewhere, cares about them enough to try and help them with research such as this!

More about the author here and here

Marching to a Different Beat: No Pulse, No Problem

Image from University Health Care System

By Amy McKean

We have seen it in countless movies and tv shows. The protagonist walks in and sees someone they care about lying down and unresponsive. This hero immediately rushes over to see if they are alive by checking for a pulse, but that may not be enough information anymore. Research into left ventricular assist devices (LVADs) have shown that we do not need a pulse to live.

Most of us have heard of pace makers, devices that can be used to aid or replace the electrical system in the heart. The electrical signal is responsible for causing muscle contractions that lead to the heart beating and the movement of blood throughout the arteries and veins of the circulatory system. Pace makers can be used when the only problem is with the electrical signal. With Heart Failure, the muscle of the heart is weak or damaged and therefore unable to sufficiently pump blood throughout the body. In this case, the problem requires more than an electrician; we need a plumber to work on the blood flow.

Many cases of Heart Failure do not require the replacement of an entire heart, but rather, the heart just needs some help. LVADs have been providing this assistance for a few decades now. They provide an alternative path for blood to travel and be pumped throughout the body. Initially these devices attempted to mimic the pumping action of the heart by using positive displacement pumps. This style of pump has a chamber that fills with liquid and is forced out by the chamber reducing in size. While these pumps worked to an extent, there were still problems such as size and reliability. A better pump required marching to a different beat.

Centrifugal and axial flow pumps are different than positive displacement pumps and work by the rotation of an impeller blade. The blood flowing through such a device will move continuously and not have the natural beat pattern observed in our heart. The full effects of removing an individuals pulse are still under investigation, but what is known is that these devices can be used to help prolong an individual’s lives successfully. If you come across someone alive, but without a pulse, they are probably not a zombie. They likely are closer to a cyborg, with a mechanical device operating in place of their heart.

More about the author

2 different types of LVAD (Rogers et al., 2017)

The little-known link between hearing loss and depression

Comic by Stromoski, continued below

By Maryse Thomas

Hearing loss is often thought of as an inevitable, harmless, and sometimes comical part of aging. However, research is increasingly linking age-related hearing loss to several other chronic health conditions, showing a need for it to be taken more seriously. These include depression, cognitive decline, dementia, diabetes, and heart disease. Among these conditions, depression is one of the most prevalent and is present in 5-10% of hearing impaired individuals.

A possible link between depression and hearing loss may relate to the social aspects of being hard of hearing. People with hearing loss frequently experience difficulties with communication, which can result in strained personal relationships, social isolation, and loneliness. In turn, feelings of loneliness can lead to anxiety, depression, and a diminished overall quality of life. Problems with communication can also negatively affect the lives of family members and caregivers, something that hearing-impaired persons are not always aware of.

Although this path from hearing loss to depression makes sense, it is important to point out that most studies linking depression and hearing loss cannot establish the direction of the relationship. More explicitly, it is still unknown whether hearing loss causes depression, depression causes hearing loss, or whether both hearing loss and depression are caused by something else. This is also true for other chronic conditions that have been linked to hearing loss, indicating that more research is needed to fully understand the connection.

Regardless of the direction of the relationship, treating hearing loss using hearing aids has been shown to have a positive effect on quality of life and to reduce symptoms of depression, loneliness, and anxiety. While some people may feel uneasy about wearing a hearing aid at first, the earlier their hearing can be corrected, the better the outcome for their mental health. Knowing that hearing loss is a risk factor for various chronic conditions, it is important to look out for their symptoms so that Grandpa’s inability to keep up with conversation at the dinner table can be treated instead of endearingly laughed off.

More about the author here and here

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