Exercise keeps brain connections alive

Casaletto K et al. Late‐life physical activity relates to brain tissue synaptic integrity markers in older adults. Alzheimer’s & Dementia, January 2022.

Physical activity has myriad benefits, including enhancement of cardiovascular health, lowering blood pressure, and promoting mental health. A recent study showed that when older adults stay physically active, their brains are activated to produce more of a protein type that enhances the connections between neurons to maintain healthy cognition. The beneficial effects of physical activity on cognition have been shown in many times in laboratory animals but it has been much harder to demonstrate in people. Neurons are separated from each other by tiny clefts known as synapses. Nerve signals that travel along the nerve cells must cross these gaps for the information to reach its destination. Synaptic proteins located at the vicinity of synapses are tasked to provide the chemical mechanism whereby information is transmitted and link the neurons into cognitive networks. In this study, the late-life physical activity of 404 elderly people, who agreed to donate their brains when they died, have been tracked through annual actigraphy monitoring. Next, their postmortem brain tissue has been analyzed for the levels of key synaptic proteins. Strikingly, elderly people who remained active had higher levels of synaptic proteins that are known to facilitate the exchange of information between neurons.

Researchers also found that increased synaptic proteins were not limited to specific cognitive-related brain regions; physical activity seemed to exert a global effect on brain connectivity beyond the parts of brain that are directly involved in cognition. Maintaining the integrity of these connections between neurons may be a key protection for the age-related cognitive disorders such as dementia and Alzheimer’s. Physical activity is a readily available medicine that can boost our cognitive and mental health, free of charge and with no prescription. This study emphasizes one more time that we should continue being physically active, particularly as we age.

Oxygen production by microbes without sunlight

Kraft B et al. Oxygen and nitrogen production by an ammonia-oxidizing archaeon. Science, January 2022.

Oxygen is vital for life on Earth. Most oxygen on land and in the sea is produced

as a result of photosynthesis, a process in plants, algae, and cyanobacteria that requires sunlight. Now a research team made a surprising discovery that some deep-sea microbes are also tasked to produce oxygen but in a completely different way. By investigating these microbes which live deep in the darkness, the researchers have focused on a microbe named Nitrosopumilus maritimus, which was previously found out to be converting ammonia to produce nitrogen by using oxygen. The team decided to observe these microbe cultures in airtight containers that are kept in the dark to mimic the deep ocean conditions. They have found that these cultures first used up all the oxygen in the water, and then to everyone’s surprise, within minutes, oxygen levels started increasing again. At first glance, they seem to produce just enough oxygen for them to survive and scientists thought that these low levels may not possibly be enough to influence oxygen levels on earth. However, when this effect is considered at a global scale, it is conceivable that the oxygen produced by Nitrosopumilus maritimus can be quickly taken by other nearby organisms. This means that this microbe is ultimately contributing to overall oxygen levels in oceans, if not for the whole atmosphere. The exact mechanism of how these archaea bacteria can produce oxygen without light is not known and it has been now the focus of future research efforts. This study opens up the possibility that there may be many different deep sea species with a whole different metabolism functioning. It also emphasizes the importance of studying and protecting the deep oceans.

70 mysterious rogue planets discovered

Miret-Roig N et al. A rich population of free-floating planets in the Upper Scorpius young stellar association. Nature Astronomy, December 2021.

Rogue planets are the freely floating cosmic objects in our solar system that roam the universe on their own without orbiting a host star. Scientists knew very little about these planets until now. A team of astronomers using data from several telescopes worldwide identified at least 70 rogue planets in the Milky Way. Since rogue planets are not illuminated by a nearby star, they used to be almost impossible to capture and image. After few million years of their formation, these planets are still hot enough to glow and become detectable by extra sensitive cameras in large telescopes. After extensive analyses of all the data they could gather revealed at least 70 rogue planets and up to 170 candidate planets that are close to a star-forming region near the Sun, located within the Scorpius and Ophiuchus constellations and 420 light-years from Earth. These findings suggest that there could be many more of these planets roaming the galaxy. Rogue planets could have been either formed from a cloud of gas and dust – the same way stars do – or they could have once been a part of a star system before getting ejected. The team hopes that by studying the large group of rogue planets, they will be able to identify their origins and how they formed and evolved. New developments in space-watching technology are very encouraging for astronomers, as they hope that by studying this large group of rogue planets, they will be able to understand their origins and ultimate fates.

Think of a kitchen. This kitchen has a blender for blending, an oven for cooking, a fridge for cooling, utensils for eating, a dishwasher for cleaning, pans for frying, jars for storing, peelers for peeling, etc. It has a full line of tools, gadgets, and appliances for the sole purpose of helping us prepare a meal. However, they are all separate appliances that altogether fill up an entire room. The fridge is not connected with the oven, nor do the forks have anything to do with the blender. Now, think of such a kitchen in which all of these gadgets and appliances work together in perfect harmony. The fridge cools some strawberries and passes them to the blender, which blends them into a tasty juice. The blender then pours this juice into a glass and serves it to you. After you are done drinking, the dishwasher kindly asks for your glass and washes it before putting it back into your cupboard. Oh, by the way, this kitchen fits snugly into your backpack so you can have juice on the go. This sounds a bit too good to be true, doesn’t it? How could every appliance be in perfect sync with all the others? How would it keep itself clean? How could all of this equipment be so compact? There would be so many complications and barriers to building such a system.

Now, what if I told you that such a system has already been built? And it’s not just a kitchen; it’s an entire palace. Our body is a marvelous palace with millions of functions and features. Such a purposeful design must have certain principles, some of which are efficiency, cleanliness, ease-of-use, and unity. Everything within our body is interconnected and works in total sync. Each organ plays its own crucial part and together they perform amazing feats. In this article, I will try to write about one player on this team: our lungs.

Our lungs serve a very important purpose: to provide the energy our body needs. Our body is in a constant state of activity. Even when we sleep, our heart pumps, our kidneys filter, our liver detoxifies, and our brain computes. No organ really ever shuts off. Maintaining such a machine is no easy task and it requires a constant source of energy. Each cell has its own generator and is more than capable of producing its own energy. However, a few things are needed to keep these generators running, one of which is oxygen. Every cell in the body needs to be constantly served oxygen as their operations begin to get disrupted only within a few minutes of an oxygen shortage. We know that our blood is full of this miracle gas, but how does it get there in the first place? We all know that it gets there through our lungs, however it is not that simple! The air that reaches our lungs cannot be too much or too little, too hot or too cold, or too dry or too wet. It has to be just right! There are impeccable mechanisms in play to perfect the conditions for each and every breath. Now, take a deep breath and keep reading!

Let us begin with how we bring air into our bodies in the first place. When we take a deep breath we actually control our diaphragm, not our lungs. The diaphragm is a membrane-like muscle that separates our abdomen from our chest cavity. It is the muscle that we move downwards when we initiate a breath. The bases of our lungs are stuck onto our diaphragm; so when we move our diaphragm downwards our lungs are also pulled down and increase in volume. This sudden increase in volume generates a negative pressure inside of our lungs causing air from the atmosphere to pour in. In addition, our exhalation occurs on its own without using any energy! Our lungs are very elastic, meaning they “want” to return to their original form similar to that of a rubber band that will snap back to its original position after getting stretched. So, after we stop contracting our diaphragm our lungs shrink back to normal and exhale air in the process. Furthermore, since breathing is semi-automatic we contract our diaphragms without even thinking about it. Most of the time, our brainstem takes care of this process without even bothering our brain. Imagine if we had to willfully inhale and exhale every breath; we wouldn’t have much time or concentration to do anything else! As you can see, this life-or-death mechanism is extremely cost-efficient and uses very little energy and little to no brainpower.

Mouth and nose

Moving onward, the beginning of the journey of air, in relation to our bodies, begins with the mouth and nose. Air is dry and its temperature can vary greatly depending on where we live or which season it is. Our body’s core temperature must be kept at a certain level for it to function optimally. Even if we wear the thickest jacket during winter, the air we breathe finds its way into the center of our body. If it weren’t for our nose and mouth this air would quickly dry up and chill our lungs. Tiny blood vessels on the surface of our nasal mucosa provide the majority of the warmth for the air that enters our nose, and the amount of blood flowing through them is regulated based on the heat of the air we breathe: more blood for colder air and less for warmer. These blood vessels also provide the moisture that is picked up by inhaled air before it enters our lungs. In addition, since the air we exhale is already warm and moist part of that moisture condenses back onto the mucosa before leaving our body. Just like a mirror fogs up when we exhale onto it, our nose and mouth are moistened with every exhalation as well. This simple, yet efficient, system is able to warm and moisturize every single breath we take while making sure no drop is wasted!

Cilia

Now, let us venture a bit deeper into our respiratory system. Unfortunately, the air is not sterile and is full of billions of microorganisms floating around. Therefore, we inevitably take in hundreds of thousands of germs with each breath. Lucky for us, but not so lucky for these germs, our respiratory tract is covered with mucus and lined with thousands of “cilia.” Cilia are specialized tentacle-like extensions found on the cells all throughout our respiratory tract. These tentacles constantly grab germs from the air, just like a dust roller grabs dust from a rug. Not only do they grab germs, they push them back outside of our lower respiratory tract. This pushing motion is performed in the form of synchronous waves by all of these tentacles and brings our germ-filled mucus back to our throat. From there, it is typically swallowed into our stomach where the acid melts it away. If we are sick and have an increased load of mucus, emergency measures like coughing or sneezing assist to evacuate the excess. Only certain bacteria that are resistant to being captured by our cilia make it into our lungs and quite a few need to penetrate our defenses to lead to an infection. Our respiratory system greatly exposes itself to the environment by taking in thousands of liters of air every day, and each breath can be considered an attack wave of bacteria and viruses. Yet, it manages to keep itself sparkling clean and ever-vigilant for the next wave.

Lungs

We finally made it to our lungs! Our respiratory tract was able to draw in the dry, cold, germ-infested air from the atmosphere, warm it, humidify it, clean it, and carry it to our lungs. After this long journey (that lasts a few seconds), it is finally time to extract that valuable oxygen! For this extraction to occur air needs to come in contact with blood vessels. The larger the area of this contact is, the better. Our lungs are designed to maximize this contact by distributing the air to a large surface area. When we take a single breath, which is about 3 liters of air, it is distributed to a surface area of nearly 70 m². This is possible because our trachea (windpipe) branches out many many times to eventually form over 700 million tiny air sacs called alveoli. This masterful dispensation allows us to extract the maximum possible amount of oxygen from each breath and deposit it into our blood. By the way, as if it was known ahead in time that many people would adopt harmful habits like smoking, lungs are made to branch into many more alveoli than we need to live, to prepare for possible damage.

In addition, the amount of air taken in with each breath is also carefully regulated. Our lungs are very flexible and can accommodate twice as much air as the typical three liters we take in with each breath. Our brainstem has a respiratory control center that automatically adjusts the speed and volume of our breathing according to the amount of oxygen we need. Running a marathon? The settings are cranked up to high. Fast asleep? Well, then you don’t need so much, so they are set to low. Our brainstem is tasked to sense our need and nurture us accordingly each and every second, and we do not need to worry about it. Try to imagine if this process was left to our management!

Our lungs also keep a small amount of air that is left inside no matter how hard we try to exhale. This volume of air is called the “residual volume” and it keeps our lungs from collapsing, which would prevent air from entering the lungs. By keeping our lungs even a tiny bit inflated at all times, we drastically reduce the energy required to breathe in. The process is similar to how blowing the first mouthful of air into a balloon tends to be the hardest, and how the continual mouthfuls are easier and easier. Just like a balloon our lungs keep that first mouthful inside at all times so the rest is always easy to fill up. This is why a deflated lung is such a big problem, because it is nearly impossible for a person to re-inflate it by themself. It usually requires assistance from a medical ventilator to get the lung back to normal.

This article only covers a few of the hundreds of mechanisms taking place in our lungs all the time so we can survive. Each of these mechanisms performs many functions, and none of them contradict each other. On the contrary, they all work in perfect unison to provide us with a nice big breath of air. However, there are so many other micro and macro mechanisms at the atomic, cellular, organ, and system levels that constantly carry out millions of functions in our body. They all follow the same principles of efficiency, cleanliness, ease-of-use, unity, and so many more, and all come together as one living, breathing, thinking, and loving human being. Doesn’t that just take your breath away?

“God contracts and expands.” (2:245)

The heart is a fairly small muscle that beats 100,000 times a day and produces roughly 115,000 Joules of energy, enough to boil a cup of water for some tea. Like a flowing river, deoxygenated blood travels from the right side of our body to the right side of our heart via valves and chambers until passing through our lungs, where each breath we take facilitates the oxygenation of every individual blood cell with 4 molecules of oxygen. The now oxygenated blood, continues to progress, never stopping, now through the left side of the heart, again passing through valves and chambers, eventually being pushed out to the rest of our body with the help of the left ventricle. The left ventricle is the thickest, largest, strongest, and most muscular part of the heart because it has the responsibility of pumping oxygenated blood through the aortic valve and aorta to the rest of our body. If this continual circulation is ever interrupted, it can lead to catastrophic outcomes.

There are several ways this flow can be interrupted, many of which happen before birth and require immediate surgery after delivery. Congenital heart defects (CHD) are some of the most common types of birth defects, but as medical care and treatment have advanced many of the babies that suffer from them usually end up living long and healthy lives. Treatment isn’t required while babies are in their mother’s womb, because the circulation of the heart is different before the baby takes its first breaths, and there is normally a mixing of oxygenated and deoxygenated blood. CHD can be mild, like a hole in the heart between two chambers that allows the mixing of oxygenated and deoxygenated blood. Ventricular septal defects and atrial septal defects (holes in the heart) are some of the most common forms of CHD. Sometimes these defects can be resolved on their own or may not be realized until much later in life, or they may require a “patch” repair if they are larger. VSDs and ASDs are associated with Down’s Syndrome, and maternal risk factors including diabetes, obesity, and smoking. Patent foramen ovale (a hole in the heart that fails to close) is found in up to 30% of the general population. It usually requires no treatment and isn’t discovered unless complications like a stroke occur later in life by having a blood clot form, requiring the blood to then travel through the hole, and then be shot up through the aorta into the brain. All babies are born with patent (open) ductus arteriosus – the ductus arteriosus is a fetal blood vessel that allows flow from the right heart to the aorta, necessary when the baby is in their mother’s womb, but incompatible for life after the baby is born. Within the first few days of life, this blood vessel should close and eventually transform into a ligament that helps tether the pulmonary artery and aorta to each other. If closure fails and the ductus arteriosus remains patent, a continuous machine-like murmur can be heard with a stethoscope, and treatment with indomethacin is started. Untreated, a PDA would result in cyanosis (blue/gray skin) and Eisenmenger Syndrome due to decreased oxygen delivery [1].

The heart’s responsibility is not only to provide oxygenated blood to the rest of the body but to also somehow feed itself. The heart’s muscles exhaust 11.6% of the body’s total oxygen consumption in order to maintain its own contractile activity, coming in 3rd after the liver (20.4%) and the brain (18.4%). During contraction or systole, the heart pumps at 120 mm Hg to provide blood through the aorta and arteries. During relaxation, or diastole, the heart expands and allows for blood to fill into its chambers and also flow through the coronary arteries. These coronary arteries are the arteries that will feed the heart itself. Thus, in order to feed itself the heart must relax and therefore allow its coronary arteries to expand and provide blood to itself. When the heart is contracting and providing blood to the rest of the organs it is too constricted to provide blood to itself. Since these branches are located within grooves of the heart, when the heart is systole the arteries are too constricted for blood flow due to increased tension. This is especially true regarding the arteries supplying the left ventricle since it is larger and more muscular – remember this is where the aorta will branch off, providing oxygenated blood to the rest of our body.

This balance between contraction and expansion may remind some readers of the concepts of Qabd (contraction) and Bast (expansion) in Sufism or Tzimtzum in Jewish mysticism, and how one truly feeds the other thus allowing for growth through this cycle of contraction and relaxation. Tzimtzum is used to explain the process of creation, a contraction of infinity happening to give birth to a finite universe [2]. The Sufi tradition is a personal journey described as “contraction and openness are mysterious ‘bargains’ that have been made without the will or intention of the traveler. The first one blocks his or her way; the second one gives him or her wings to fly to new heights [3].” What is perhaps most interesting is that our physical heart performs this contraction and expansion perfectly so long as we take care of it, whereas our spiritual heart can have lapses in this critical exercise. Maybe, if we understand how to take care of our physical heart, we will also find the answer to keeping our spiritual heart healthy. Prophet Muhammad, peace be upon him, emphasizes this connection as follows: “Verily, in the body is a piece of flesh which, if sound, the entire body is sound, and if corrupt, the entire body is corrupt. Truly, it is the heart.”

Some ways to take care of our physical hearts include incorporating more physical activity into our daily lives, eating less and healthy, and controlling our stress. Perhaps our spiritual health would also benefit from these and similar activities, including regular acts of worship, fasting, controlling our temper, and being kind to others. When we don’t take care of our physical heart, it begins to fail since oxygen ceases to be delivered to our heart and the electrical currents can no longer travel effectively, thus resulting in a heart attack.

Coronary artery disease is the leading cause of death worldwide, and especially in developed countries. The deadliest heart attack occurs if there is a blockage of the left anterior descending coronary artery, which is why it is tragically termed the “widow maker.” Beginning from adolescence, arteries begin to accumulate fatty streaks and progress to an atherosclerotic plaque. This plaque can lead to several disastrous complications such as follows:

• a narrowing or complete obstruction of an artery, impairing blood flow and leaving the heart thirsty for oxygen
• a stroke due to a blood clot caused by decreased movement, breaking off and flowing to the brain
• a weakening of the vessel wall leading to an aneurysm, the vessel bursting

For some patients, a heart attack becomes a wakeup call in order to make the many necessary lifestyle changes that are necessary in order to live a long and healthy life. However, 20% of patients will experience a second heart attack. As the heart gets weaker and weaker it can eventually develop cardiorenal syndrome, a complication that results from the heart being unable to pump effectively resulting in it getting backed up in the heart and the right side of the body. This increase in volume in the body is further exacerbated by the kidneys, which continue to retain fluids and thus cause the body to become overloaded. This leads to edema, or swelling, in the legs that can eventually progress to the lungs and cause congestive heart failure. As the kidneys try to ameliorate the fact that the heart is not pumping effectively, they ultimately worsen the situation leading to end-stage renal disease and stage D heart failure.

Of course, as with almost all medical conditions, these fatal results can be prevented much earlier with lifestyle changes, even before introducing medical intervention with prescription drugs or other procedures. These lifestyle modifications include moderate aerobic exercise at least 3 times a week, a diet rich in vegetables and low in fats, sugars, and carbohydrates, smoking and alcohol cessation, and weight reduction (which would come as a result of these modifications). It is also important for patients that are already dealing with hypertension, diabetes, and hyperlipidemia should keep them well-managed and controlled.

Maybe similarly, some simple lifestyle changes, such as putting aside a few minutes every day to reflect, can be the secret to keeping our spiritual heart healthy. Our heart must remain healthy to keep the rest of our body healthy. Considering the close relationship between our physical and spiritual heart, our spiritual heart must be kept healthy to keep the rest of our spiritual body healthy. Spiritually healthy individuals will further reinforce the health of our community, for Prophet Muhammad, peace be upon him, says, “The believers in their mutual kindness, compassion and sympathy are just like one body. When one of the limbs suffers, the whole body responds to it with wakefulness and fever.”

“As the whole of existence is in His grasp and at His free disposal, it is He Who directs and disposes of all things, from the heavens to the human heart… When God wills, He contracts a heart so tightly for what only He can provide that only He can satisfy it. By contrast, He expands and exhilarates it to such an extent that it needs nothing. Contraction is caused by God’s Majesty; openness is caused by His Grace. (Fethullah Gülen, Emerald Hills of the Heart).”

References

• https://www.heart.org/en/health-topics/congenital-heart-defects
• https://www.britannica.com/biography/Isaac-ben-Solomon-Luria#ref163236
• http://fgulen.com/en/fethullah-gulens-works/key-concepts-in-the-practice-of-sufism-1/qabd-and-bast-contraction-and-openness

As I wheeled Chris off the elevator, he was quieter than the day before, definitely not in the mood for pranks. He didn’t complain—my husband never complained—yet he clearly wasn’t feeling as well.

Two steps forward, one step back: that still qualified as progress.

Rolling through the hospital hallways, following signs for Radiology, we passed several women wearing nasal cannulas and pulling oxygen-cylinder carts. The sight wasn’t remarkable in that the National Institutes of Health runs clinical trials on virtually every ailment—from the common to the rare, the treatable to the terminal. What was surprising was seeing a cohort of patients similarly afflicted, all female and relatively young.

At least they were ambulatory. When Chris’s doctor ordered a scan this morning, his nurse ordered a wheelchair.

During his first few days after readmission, Chris’s condition fell somewhere between depleted and God-awful depending on the degree of his sawtoothing fever. As his treatments—withdrawal of anti-rejection meds included—began to take effect, however, I’d sometimes arrive to find him sitting up in bed, looking comfortable and alert, like a patient soon to be released.

Towards the end of the week, his humor kicked in. After opening a colleague’s get-well card to find a droll reference to their firm’s new management—a buyout of the Rouse Company was but two weeks away—Chris reached for the bedside phone. When a recording advised him to leave a message, he deepened his voice and pretended to be the CEO. “This is John B—,” he said gruffly. “It’s come to my attention that you have a poor attitude about the merger.”

To me, the spoof was proof of recovery. To his friend, who didn’t recognize Chris in disguise, it was cause to call the head of security: Someone was impersonating the chief executive.

Come Friday, Chris remained frail despite signs of improvement. His nurse took me up on my offer to drive him to his appointment.

In the Radiology waiting room, we found two more women on oxygen therapy. After positioning Chris at the end of a row of seats, I took the one beside him. If silence had been a preference en route, now it was a prescription. No one spoke or made eye contact. No one leafed through magazines, for there were none. No one asked the time or glanced at their watch. It was as if chronic illness had instilled a monkish composure. Or torpor.

I was the only non-patient in the room, the Lucky One. As the others sat alone with their thoughts, I wondered what those might be. That three back-to-back tests followed? That with sick leave exhausted, the boss had to be told? That scrambled eggs might stay down? That last time the shadow had shrunk, so this time, well, don’t get too hopeful?

Or were they trying to avoid thinking, instead imagining doing something—anything—more agreeable? Strolling through the hill town of Assisi. Watching a Coen brothers film. Defending an IRS audit.

One of the women on oxygen finally had enough. Silence wasn’t a chance to grab a shot of mindfulness; silence was a looming endgame. By talking, she could ward off quietus. But she needed a partner.

“What brings you here?” she asked me, in a tone so warm and genuine that she might have been a greeter in a small-town visitors bureau.

She looked about forty, or a little older, but it was hard to tell; illness can age a person faster than a Broadway makeup artist. Although her appearance was middling in every respect—from her height and build to her facial features and shade of brown hair—her spirit was striking. Whether the vivacity was innate or cultivated for survival, she offered me what she desperately needed: a deep breath of fresh air.

“My husband needs an X-ray.” I glanced at Chris. He showed no sign of wanting to engage. Under the circumstances, it felt unfriendly, even hurtful, to not offer more. “He had a kidney transplant a few months ago,” I added. “Now he has mono.”

Immediately, another patient stood and left. Perhaps she went to the restroom, or realized she’d left her purse in the car. More likely, mononucleosis spooked her—even though it’s not an airborne infection.

I paused, realizing that my interlocutor might want to leave, too. She didn’t budge. “How about you?” I asked. In deference to patient privacy, I avoided the politeness of trading names.

“I need a double-lung transplant. There’s a group of us here who have the same disease. We get together every year.” She chuckled. “It’s like a reunion!”

Lymphangioleiomyomatosis, or LAM, is a rare condition that primarily affects women ages twenty to forty. Abnormal cells invade the lungs, as well as lymph nodes and kidneys, leading to reduced pulmonary function and respiratory failure. Treatments, including transplantation, can enhance the quality and duration of life but the disease is incurable. After diagnosis, life expectancy is usually ten to twenty years.[1]

Her disclosure was stunning. Not long ago, I wouldn’t have grasped the challenges she faced, merely to delay the inevitable. No longer.

One day she would lie in an OR, as we recently had. But unlike Chris, whose kidneys were allowed to fail in place, with one of mine nested beneath them, she would have both lungs removed to accommodate her grafts. No matter how damaged and inadequate, those lungs were infusing her blood with oxygen, ridding it of carbon dioxide, maintaining life. Temporarily, she might require a heart-lung machine and a ventilator; ultimately, she’d either breathe though the new air sacs or wouldn’t . . . breathe. If her grafts failed, there was no recourse like dialysis to sustain her.

In short, she would perform a death-defying, net-free launch from a trapeze with no turning back once she let go of the fly bar. Her odds of surviving even five years after transplantation were not much better than one in two.[2]

And that was if she got lucky. With the chronic shortage of deceased-donor organs, lungs might not become available in time. Although living donation was possible, she’d need two Good Samaritans, each providing the lower lobe of a lung.^⁠ They’d face a riskier surgery and longer recovery than kidney donors, which meant friends and relatives were less likely to volunteer.

A radiology assistant called Chris’s name. Together, they disappeared through a door leading to the imaging machines. Moments later, the woman was called, as well.

She’d shared no details about her personal life. She’d only spoken of her illness, which, understandably, had come to define her—from what lung-healthy products she could buy to how she should dress, walk, or perform daily chores, such as unpacking groceries, to minimize exertion. If she seemed compelled to tell me she had LAM, it was not because she sought sympathy; she struck me as someone devoid of self-pity. What she wanted was to be heard. To be heard is to be remembered.

In no time, Chris was back and we were retracing our route through the cold fluorescence of the corridors. As we entered an empty elevator, he said, “You shouldn’t have mentioned I have mono.”

“Why?”

“You saw the woman leave.”

“But she had a right to know. I’d want to know.”

I hadn’t meant to embarrass him. For that I was sorry. But I was as disappointed in him as he was in me. Chris was still “chesting” his health cards, as if this were a hand of bridge, with nothing but his pride at stake.

No doubt a gender difference was at work, a primal XY-chromosome trait, which he’d exhibited many times before: Never show weakness lest a contender seize the advantage—be that your mate, your kill, or your year-end bonus. According to such logic, illness fell between failing and fatal flaw.

A strategy suitable for the savanna or a boardroom, however, is counterproductive in a medical setting where any debility you don’t reveal is one that isn’t treated. The woman I’d just met understood the importance of communication, on every front, regarding her health. I was sorry that my husband didn’t.

And hadn’t.

At the same time, I was grateful. As we made our way back to his room, my mind unspooled a skein of “at leasts.” At least he isn’t suffocating to death. At least he can fall back on dialysis. At least he isn’t alone while undergoing treatment. At least his graft shows no sign of rejection. At least I haven’t had to kiss him goodbye outside an OR and wonder if he would return. At least both of us were able to presume we would return.

Counting blessings was my luxury, not Chris’s. Sick as hell, he was entitled to feel however he felt, unthankful included, with no obligation to parse his advantages relative to others.

Later that night, Chris’s doctor called me at home. He’d had Chris moved to intensive care. He spoke so calmly and matter-of-factly that I didn’t panic. In fact, the thought never occurred to me that every “at least” would soon count for nothing.

[1] National Heart, Lung, and Blood Institute, “Health Topics: LAM,” http://www.nhlbi.nih.gov/health/health-topics/topics/lam (accessed February 1, 2019).

[2] Organ Procurement and Transplantation Network, “National Data: Lung Kaplan-Meier Patient Survival Rates For Transplants Performed, 2008 – 2015; Survival by Single vs. Double Lung (Lung Only),” https://optn.transplant.hrsa.gov/data/view-data-reports/national-data/# (accessed February 2, 2019).

Research on hummingbirds (also known as nectar birds or Colibris), the smallest of the 9,800 bird species living today, has revealed remarkable facts. The world’s smallest birds are equipped with mind-blowing structures and functions that push all physiological and anatomical boundaries. The bee hummingbird (Mellisuga helenae), considered to be the smallest bird in the world, is only 1.96-inch-long and weighs 0.06 ounces.

There are around 330-340 species of hummingbird and they live only in North and South America and the nearby oceanic islands. With their colorful feathers, they are some of the most beautiful birds.

How the hummingbird flies

A hummingbird flaps its wings so fast that the motion cannot be seen by the human eye but only detected through special cameras. The wings move at an incredible speed in a seemingly complex pattern, drawing circles back and forth 50 to 80 times per second, depending on the species. Under the genus Colibri, the horned Sungem (Heliactin bilophus) species flaps its wings 90 times per second; the purple amethyst Colibri (Calliphlox amethystina) flaps its 80 times per second. This speed increases up to 200 per second during a short spike while escaping from an enemy. Moving back and forth, the wings oscillate in the form of the figure 8 in the air. While in most other birds the movement of the wings produces the power to lift up and down, Hummingbirds, like helicopters, can perform movements such as hanging in the air or standing steadily as well as flying backward or rising in a vertical direction.

Figure 8

Metabolic rate and energy consumption

Flying requires a lot of energy. The amount of energy spent is related to the bird’s body size and flapping speed. In this regard, given that a colibri flaps its wings 80 times per second, it takes a great deal of energy to maintain such a rapid movement. The colibri’s chest muscles were perfectly created for flapping quickly and take up 40% of the hummingbird’s total body mass. Therefore, a colibri consumes more energy than other birds; it’s basically a fighter jet.

In order to meet this high energy demand, the amount of nectar a colibri consumes every day has to be equal to their body weight. Living at such a high metabolic rate requires a fine adjustment of food consumptions with precise calculations.

Such a high food intake requires a high metabolism – and thus, the need for oxygen increases dramatically. When the need for oxygen increases, there can be two kinds of conditions. Those animals with very large lungs can intake a lot of air at once. And those with smaller lungs can produce the required oxygen by breathing many times a minute. Colibri or Nectar birds are the ones that can breathe the most in one minute. The lungs of the world’s smallest birds breathe 250 times per minute to transfer oxygen to their hearts weighing a mere 0.003 ounces and beating 1,200 times per minute.

Toronto University’s Kenneth C. Welch Jr. studied the metabolism of hummingbirds for more than 10 years. He discovered that there is a relationship between the size of hummingbirds, energy efficiency, and oxygen consumption, and that larger hummingbirds are more efficient energy users than smaller ones. A hummingbird can take 2.44 cubic inches of oxygen per 0.03 ounces an hour. When a small weight is added to the bird, this amount increases to 3.66 cubic inches, and their tissues use oxygen very efficiently.

Energy requirements

A hummingbird’s metabolism is the fastest among all vertebrates. It needs to eat almost constantly to get the energy it needs to produce fuel for its breathtaking metabolism, which functions like a power plant. It receives nectar from 2,000 flowers every day. If we humans could work at this bird’s energy levels, we’d have to eat about 1,300 sandwiches a day to produce energy, and our body temperature would rise to 725 °F! Also, our hearts would have to beat 1,260 times per minute. Although nectar from flowers is the main fuel source driving the bird’s metabolic engines, it also occasionally eats insects, for protein needs.

During any given 30-minute period, hummingbirds burn the sugar they had taken in an hour ago. If we apply this rapid intake of sugar and the metabolic cycle in human beings, we would have to drink a large bottle of soda and burn the sugar in it every minute.

Unlike us, hummingbirds use both glucose and fructose from nectar in their intestines, circulatory systems, and muscle cells. However, we can support our bodies at urgent needs with an intake rate of 30% of glucose. Half of the nectar that hummingbirds take is glucose and half is fructose. In this modern age, high fructose derived from corn in our diets has paved the way for metabolic diseases and obesity – that is, people cannot metabolize high fructose.

Scientists are trying to determine how hummingbirds can process fructose. It is known that there is a carrier molecule different from glucose in fructose. This carrier is very rare in human muscle cells, but it is found in abundance in hummingbird’s muscle fibers; so we believe the mystery of how they utilize fructose so fast is about to be solved.

Hummingbirds have been equipped with mechanisms to increase the rapid introduction of nutrients such as fructose and glucose – which are basically small sugar molecules – or amino acids into their metabolisms. Their hearts and blood vessels work at a high speed to carry the sugar into their tissues as well as to transfer a lot of blood. In addition, a large number of capillaries have been implemented close to the muscle cells so that the blood can reach each and every cell.

Wing design

While humanity has not yet invented a machine that can move in a figure-8 pattern 80 times per second, including forward and backward, the ultra-flexibility of a hummingbird’s unique wing strokes demonstrates the special creation of its bones, muscles, and joints. The colibri’s brain and nervous system, which control these muscles and joints by transmitting signals, require infinite knowledge and power. The flexibility of the shoulder joint in the movement of the wings, which allows them to bend to extreme positions not found in other birds, gives us an idea of the wing’s unique design and architecture. Although biomimetic engineers have spent millions of dollars applying this complex system to technology, they have so far failed in their attempts to produce a similar machine.

Cooling the feathers due to the friction of the muscles and the tremendous movement of the wings is a problem in itself. While man-made machines need advanced cooling systems, the hummingbird has been created with a such a built-in system.

Unique tongue structure

Biologists from the University of Connecticut have discovered that hummingbirds’ tongues have a very special design and work like micro pumps. Tongues about twice the length of their beaks allow them to reach deep into flowers. The nectar is then pumped into the body in less than 1/20^th of a second. This occurs thousands of times each day. Tai-Hsi Fan and Margaret A. Rubega, who for a long time examined how hummingbirds stick their tongues 15 or 20 times a second into the tubular part of a flower, said that they “could not clearly understand how they drink the nectar.” In their latest study, they showed that it was only possible for the birds to hold nectar through two channels in their tongues. It was once thought that the physical rule of the upward movement of liquids in capillary tubes, even without suction, worked in the hummingbird’s nectar intake; but when special video recordings of the movement of their tongues were examined, it became evident that the tongue first compressed the nectar in a series of movements, then sprung up very quickly and the nectar was suddenly sprayed into the channels.

It would seem that both the hummingbirds and the flowers they need for sustenance were created in perfect harmony.

Red hummingbirds migrate from Alaska to Mexico every year. They can fly 56 miles per hour. Prior to this journey, they feed for one or two weeks to fill their fuel tanks, forming a layer of fat equal to half their body weight. Since these activities cause a lot of heat loss on the body surfaces, they cannot provide enough energy to stay active for more than 12 hours at a time. To counter this, they fall into a deep sleep every night for 12 hours. The energy storage, flight endurance, long-distance migration, and returning with the young ones are each complicated factors that their coming together to make this journey possible cannot simply be explained by blind chance.

Of course, the smallest bird in the world would have the smallest egg size: a mere 0.5 x 0.3 inches, for a total weight of 0.007 ounces. Considering that this wonderful bird’s design is embedded into this egg, which is about the size of the nail of our little finger, it can be understood how perfect a creation it is.

Global Climate Report. NOAA National Centers for Environmental Information (http://www.ncdc.noaa.gov). July 2019.

It’s summer, and it is hot out there; but if it feels like record-breaking temperatures are becoming more common globally, they are. The National Oceanic and Atmospheric Administration and European Copernicus Climate Change Service announced that July 2019 was the hottest month across the globe ever measured since measurements began, in 1880. Global temperatures averaged 16.73°C in July, which is 0.95 °C higher than the 20th-century average of 15.78°C . Average Antarctic sea-ice coverage was 8.5% below the 1981-2010 average. And sea ice coverage was 10.5% below the overall average, which is based on records beginning in 1979. The scientists also released geographical data, showing that the regions where temperatures varied furthest from averages, were Alaska, Central Europe, Northern and Southwestern parts of Asia, and certain regions in Africa and Australia. These findings corroborate scientific predictions regarding the effects of man-made climate change. Human activities, primarily from burning fossil fuels, emit carbon dioxide and other greenhouse gases that trap heat in the atmosphere. Increasing greenhouse gas emissions are associated with warmer global surface temperatures. The planet’s 10 hottest years on record have all fallen in the past two decades. Scientists and policymakers around the globe are also feeling this heat.

Unless significant measures to curb greenhouse gas emissions are adopted, scientists expect temperature records to keep falling. Scientists say global temperatures could increase by at least 3°C this century, which will create conditions on Earth that have not been seen in more than 2 million years. Given the notable trends in higher temperatures and natural disasters, we might be pushing the climate system toward states that we haven’t seen in our societal experience – and even in our species’ experience.

Manipulation of brain circuits using smartphone-controlled device

Qazi R et al. Wireless optofluidic brain probes for chronic neuropharmacology and photostimulation. Nature Biomedical Engineering, August 2019.

Scientists recently designed a device that can regulate brain circuits using a tiny brain implant controlled by a smartphone. This bluetooth-enabled device utilizes replaceable lego-like drug cartridges to target neurons with drugs and light. Existing methods to deliver drugs and light to the brain typically involve metal tubes and optical fibers. These tools are rigid and can substantially damage the brain’s soft tissue over time. Moreover, this bulky equipment often limits the patient’s movement because of the wired connections, making them unfit for long-term use. To achieve chronic remote-controlled drug delivery without exhaustion and evaporation of drugs, scientists invented a neural device with a replaceable drug cartridge, which could allow neuroscientists to study the same brain networks for several months without depleting the drug supply. These “plug-n-play” drug cartridges were integrated into a brain implant for mice with a soft and ultrathin probe (about the thickness of a human hair), which consisted of microfluidic channels and tiny LEDs (smaller than a grain of salt), for unlimited drug doses and light delivery. The implant is regulated via a smartphone, allowing researchers to trigger precise combinations and sequences of drug and light delivery. In animal models, these stimuli can be triggered with the target outside of the laboratory, allowing researchers to wirelessly instill changes in the animal’s brain while in its natural habitat. Using these neural devices, researchers are now able to perform fully automated animal studies where the behavior of one animal could positively or negatively affect behavior in other animals by conditional triggering of light and/or drug delivery. This device will allow researchers to better dissect the neural circuit basis of behavior and how specific neuromodulators in the brain tune behavior in various ways. In addition, the device can be utilized in complex pharmacological studies to develop potentially new therapeutics for pain, addiction, and emotional disorders.

The secret weapon of E.Coli 

Melson E. at al. The sRNA DicF integrates oxygen sensing to enhance enterohemorrhagic Escherichia colivirulence via distinctive RNA control mechanisms. Proceedings of the National Academy of Sciences, June 2019.

Scientists have revealed how E. coli (Escherichia coli) bacteria seeks out the most oxygen-free parts of your colon to cause the worst infection possible. E. coli normally live in the intestines of healthy people and animals. Most varieties of E. coli are harmless or cause relatively brief diarrhea. But a few particularly nasty strains can cause cramps, diarrhea, vomiting – even kidney failure and death. Children are particularly at risk. A new study uncovers how this foodborne pathogen knows where and when to begin colonizing the colon on its way to making you sick. Bacterial pathogens typically colonize a specific tissue or organ in the host. Therefore, as part of their infection strategies, bacterial pathogens precisely time deployment of proteins and toxins to these specific colonization niches in the human host. This allows the pathogens to save energy and avoid detection by our immune systems and ultimately cause disease. The researchers in this study identified how E.Coli detects low oxygen levels in the large intestine and then produces proteins that allow it to attach to host cells and establish infection. Oxygen actually diffuses from the intestinal tissue into the gut, and there are comparably higher levels in the small intestine than the large. Remarkably, E. coli specifically waits until it has reached the-low oxygen large intestine before striking. E. coli controls this process via a small form of RNA that activates particular genes when oxygen levels are low. This is the point when the infection really gets established and the bacteria are able to begin to manufacture harmful Shiga toxins. The researchers predict that other bacterial pathogens, such as Shigella and Salmonella, likely utilize a similar control mechanism. Researchers suggest that if we can find a way to block oxygen sensing, we may be able to prevent the infection by allowing E. coli to pass harmlessly through the body.

Biggest extinction in Earth’s history caused by global warming—and how it could happen again

Penn JL et al. Temperature-dependent hypoxia explains biogeography and severity of end-Permian marine mass extinction. Science, December 2018.

Some 252 million years ago, long before dinosaurs, the vast majority of species on Earth were wiped out in the “Great Dying,” the worst mass extinction in our planet’s history. Up to 96% of all marine species and 70% of land animals were killed off during this event. Scientists have been trying to find the cause for this catastrophic event, which marked the end of the Permian period. One study suggested that a type of microbe spouted large amounts of methane into the atmosphere. Other studies suggested the event was triggered by a series of volcanic eruptions that released deadly amount of carbon dioxide into the air and led to cataclysmic ocean acidification. A new research study now claims that the Great Dying was primarily as a result of rapidly increasing temperatures. The researchers examined the marine fossil records and simulated the climate conditions to observe the effects of rising temperatures 252 million years ago. Researchers first ran a climate model with Earth’s configuration during the Permian period, when the tropical ocean temperatures at the surface had reached some 10 degrees Celsius (50 degrees Fahrenheit) higher. The model then reproduced dramatic changes in the oceans; oceans lost about 80 percent of their oxygen and about half the oceans’ seafloor became completely oxygen-free. To investigate the effects of these paleoclimate changes on marine species, the researchers then analyzed the varying oxygen and temperature sensitivities of 61 modern marine species including crustaceans, fish, shellfish, corals and sharks. Their calculations predicted that many marine organisms went extinct under these conditions, especially the organisms that lived far from the tropics were most sensitive to oxygen levels and they were nearly completely wiped out. To test this prediction, researchers analyzed late-Permian fossil distributions from the Paleoceanography Database and confirmed that species far from the equator suffered most during the event. The agreement between the simulations and fossils strongly suggests that climate warming and oxygen loss was a primary cause of the extinction. By 2100, warming in the upper ocean is projected to approach 20 percent of warming in the late Permian, and by the year 2300 it will reach between 35 and 50 percent. This study highlights the potential for a mass extinction arising from a similar mechanism under anthropogenic climate change. It is also a clear warning that Earth is on the path to another devastating mass extinction. According to experts, Earth could already be undergoing a sixth mass extinction that would kill off most animal and plant species. The International Union for the Conservation of Nature predicts that 99.9% of critically endangered species and 67% of endangered species will be lost within the next 100 years.

New target for therapeutic brain stimulation to treat depression found

Rao VR et al. Direct Electrical Stimulation of Lateral Orbitofrontal Cortex Acutely Improves Mood in Individuals with Symptoms of Depression. Current Biology, November 2018.

Researchers have finally found an effective target in the brain for electrical stimulation to improve mood in people suffering from depression. Stimulation of a brain region called the lateral orbitofrontal cortex (OFC) reliably produced acute improvement in mood in patients who suffered from depression. In a recent study, researchers studied 25 patients with epilepsy who had electrodes placed in the brain for medical reasons to locate the origin of their seizures. Many of those patients also suffered from depression, which is often comorbid with epilepsy. With the patients’ consent, researchers took advantage of those electrodes to deliver small electrical pulses to areas of the brain thought to be involved in regulating mood. The researchers focused their attention and the electrical stimulation on the OFC, which is a key hub for mood-related circuitry. Moreover, they specifically induced a pattern of activity in brain regions connected to OFC that was similar to patterns seen when patients naturally experienced positive mood states. The researchers applied these stimulation regimes while collecting verbal mood reports and questionnaire scores. Analyses of these reports revealed that unilateral stimulation of the lateral OFC produced acute, dose-dependent mood-state improvement in subjects with moderate-to-severe baseline depression. There is still substantial work remains to be completed before the deep brain stimulation (DBS) treatments could enter routine clinical practice. One major challenge in this study is to see whether stimulation of OFC produces durable improvement in mood over longer periods of time. Biomedical engineers hope to develop a medical device for patients with treatment-resistant mood disorders that can monitor brain activity in OFC and stimulate only when needed to keep that activity within a healthy range. Ultimately, it would be ideal if activity in mood-related brain circuits could be normalized indefinitely without patients needing to do anything.

How screen time can disrupt sleep

Mure LS et al. Sustained Melanopsin Photoresponse Is Supported by Specific Roles of β-Arrestin 1 and 2 in Deactivation and Regeneration of Photopigment. Cell Reports, 2018

For most of us, the time spent staring at screens on computers, phones and tablets adds up to many hours in a day and can often disrupt sleep. In a recent work, researchers now have pinpointed how certain cells in the eye process ambient light and reset our internal clocks, the daily cycles of physiological processes known as the circadian rhythm. When these cells are exposed to artificial light late into the night, our internal clocks can get confused, resulting in a host of health issues. A protein called melanopsin in these light-sensitive cells helps them process ambient light. Prolonged exposure to light causes melanopsin to regenerate and continuous regeneration of melanopsin triggers signals to the brain that inform it about ambient light conditions. The brain then uses this information to regulate sleep, alertness, and consciousness. In this study, the researchers turned on the production of melanopsin in retinal cells in mice and found that some of these cells are able to sustain light responses, but others lose sensitivity. Further investigations found that proteins called beta arrestin-1 and beta arrestin-2 help keep the melanopsin sensitive when exposed to light. One arrestin does its conventional job of arresting the response, and the other helps the melanopsin protein reload its retinal light-sensing co-factor. When these two steps are done in quick succession, the cell appears to respond continuously to light. This research uncovers the mechanisms behind how cells being exposed to artificial light confuses the internal body clock, and the ability to regulate sleep. It is hoped that this discovery could lead to new targets that could counter the impact of artificial light, for example by finding ways to influence melanopsin to reset the internal clock. This could lead to new treatments for insomnia, jet lag, and migraines.

We live in a magnificent world inhabited by approximately 8,700,000 species. This number includes only general species, not subspecies. Scientists discover around 2,500 new species every year, and the number is soon estimated to reach 10 million.

All living organisms are blessed with unique bodies, systems, and organs, defense and protection mechanisms to survive and protect themselves, and special features to help them forage for food.

When people get ill due to environmental effects or malnutrition they usually consult a doctor. They try to find a cure by using the medicine prescribed by doctors. However, animals living in the wild don’t have this option. When animals living in nature or on the street get ill what can they do if nobody takes them to a vet? How do millions of species get well and find cures for their ailments?

You might think that animals who become sick in the wild must simply live with their symptoms, but this is not the case. In fact, we have given a clue at the introduction: each organism is equipped with features to lead a self-sustaining life. Either their bodily functions perfectly enable them to live in their habitat or their unique metabolisms protect them from harmful external factors. Animals also can use some plants whose health benefits have only recently been discovered by humans.

In recent decades, there has been a growing interest for herbal products such as walnut leaf, cherry stalk tangerine rind, grenadine red, and celery root to find cure for diseases.

Animals perform amazing tasks with mind-blowing adroitness as if each were an expert chemist. Wondrous mechanisms are activated when a need arises to protect animals from harm.

Some plants with healing properties:

Lupine, quassia, bitter wood, hemlock, fishberry, roselle, henbane, giant fennel root, pistachio, resin, pine turpentine, mistletoe, cumin, hibiscus, hibiscus flower, alkanet, flos elaeagni, camphor, cardamom, St John’s wort, French lavender, Flaxseed, linseed oil, henna tree, quillaia, wall germander, cranberry, aspand, daffodil, water lily, common balm and eucalyptus.

Animals have been consuming and finding cures in these plants since the dawn of time. They are also equipped with many surviving capabilities under extremely severe conditions. Here are a few examples:

Antibiotics expert

With a height of up to five meters, the giraffe is the tallest land animal. Scientists who investigated the scent emitted by the giraffe found 11 separate chemical substances in its fur. The chemicals turned out to have antibiotic properties, having an increased efficiency when combined. Only after a series of experiments can these incredibly complex chemicals be extracted in the laboratory. The giraffe has been using these chemicals to prevent fungi and bacteria, repel ticks, and stop the growth of germs. Where did these tall creatures study chemistry to know how to produce antibiotics such as indole?

The stubborn doctor

The bezoar ibex is a type of mountain goat native to Turkey, Iran, Turkmenistan and Pakistan. It has a motley coat of black, brown, grey, reddish-gold, and white. Both the male and female have horns and a goatee. The name means “cure” in Persian, and the locals must have noticed its habit of eating spurge whenever bitten by a snake. Scientists have identified the substance called euphorbone in the spurge plant. Amazingly, an analysis of this substance reveals that certain chemical reactions triggered by euphorbone neutralize the effects of venom. The poisoned creature looks for splurge from among the vegetation, self-medicates, and treats itself free of charge. It sure is no wonder when one realizes that the goat, the snake, and the plant are all created by the same hand.

The master of diving

Divers who ascend too quickly to the surface run the high risk of experiencing the bends, an intense pain that is likely to kill because of the gasses coming out of the bloodstream. But how do billions of creatures that lack oxygen tubes lead their entire lives in the sea without experiencing the bends?

Dolphins and whales, for example, descend to depths humans can’t reach on their own and then rise like it is no big deal. Human lungs cannot endure the pressure under such depths, but the bronchi and air sacs in the lungs of dolphins, however, are placed inside a protective cover of special cartilage. To avoid suffering the bends, dolphins release all the air in their lungs before diving deep. But how then do they breathe? The answer is hidden in their muscles, or rather in the myoglobin protein that is available in much higher amounts than in humans. These proteins have the ability to hold in high amounts of oxygen molecules. The much needed oxygen is provided from this source, enabling dolphins and whales to dive as deep as possible.

Poison for one, food for another

The macaw is an inhabitant of American tropical regions with an average wing span of 80 cm. It is known to be a tough creature that lives as long as 60 years. The macaw feeds on plants that produce a chemical called strychnine (C₂₁H₂₂N₂O₂), a powerful poison intended to ward off enemies. How can a substance that kills some living things nourish others? Immediately after eating the nutritious but poisonous seeds, the macaw flies to the rocky cliffs in a certain area. When they get there, they gnaw at and swallow some clay-based rock pieces. The fact that the bird ingests clay without any apparent reason is quite an interesting behavior. The reason was revealed only after research into the origins of the behavior. It turns out that the rocks that have clay in them include a substance called kaolinite (Al₂O₃.2SiO₂.2H₂O) that can absorb the poison in the seeds. The macaw can digest the normally poisonous seeds thanks to this absorption and live on with its life safely. There is no way the macaw can know about the substances present in the clay, so how does it know to eat the clay that can eliminate toxins?

The antifreeze expert

The arctic beetle survives against the inhospitable cold of the arctic thanks to a type of alcohol produced in its body that works as antifreeze. The glycerol (C₃H₈O₃), also called glycerin, produced by the insect prevents the blood and other fluid molecules from freezing and thus ice crystals from killing the cells and destroying cellular bonds. Furthermore, the shorter the days and the colder the weather, the more resistant the bodily mechanisms of the arctic beetle become. As the temperature drops, the volume of water in their body is reduced and antifreeze substances such as glycerol and sorbitol are produced in greater amounts. Research on this amazing creature has revealed that it can survive in temperatures as low as -87 degrees Celsius due to glycerol. It is beyond reason to expect an insect to know how to produce an organic compound with the complex formula of C₃H₈O₃ and thus protect itself from extreme cold.

The radiation expert

Scientists analyzed a surviving scorpion after an atomic bomb test, yet they couldn’t find a satisfying answer to how this animal survived the radiation shower that exterminated all other living organisms. Note that scorpions which came into existence millions of years ago are basically living fossils. Thanks to the protective system they are blessed with, in the past they have survived more powerful solar explosions and harmful radiation from outer space and the sun, and handed down these features to future generations.

The creature that never feels cold

The tardigrade, or water bear, is one of the most resistant organisms in nature.

The size of a pinhead, these microorganisms have pin-shaped hoses in their mouth.  These microorganisms have a brain, a pair of eyes, and a digestion system, but they do not have a heart or lungs.  600 different subspecies of the animal have been discovered so far. They feed mostly on moss and lichens and can survive in any environment including space.

They have been observed to survive a temperature of 120 ⁰C and a pressure of 1000 atm. In dry environments they contract, causing the water in their tissues to evaporate. During this process, the oxygen consumption of the tardigrade virtually stops. The wind carries the dried tardigrades to other places and when they find a suitable environment (wet moss or humid places) they can come back to life again.

According to Ingemar Jönsson from Kristianstadt University in Sweden who participated in studies on this organism, it is a mystery how these animals survive even when they are subjected to conditions in outer space.

Animals perform amazing tasks with mind-blowing adroitness as if each were an expert chemist. Wondrous mechanisms are activated when a need arises to protect animals from harm. It is wondrous to see how animals can carry out these complex chemical procedures as if they have been instructed at birth.

The human body is built from the elements found on earth. There are approximately 44 kg of oxygen, 14 kg of carbon, 7 kg of hydrogen, 2.1 kg of nitrogen, 1 kg of calcium, and lesser amount of other elements existing in a 70 kg human body. In fact, many of the 92 naturally occurring elements can be found in the human body, which resembles a small universe. Surely, these elements cannot act chaotically and only fulfill their duties in the organs that are assigned to them in the great mechanism of the human body.

Oxygen is one of these natural elements; under normal natural conditions, it exists in gas and molecular form (O2 and O3). It is abundant throughout the world: nearly 65% of the human body, 88% of the waters on earth, and 46.7% of the earth’s crust are made from oxygen atoms (in terms of their mass). Since it is an active element, which makes compounds with many other elements, it is found generally in compound form.

When we say oxygen, the first thing that comes to mind is the oxygen we breathe in the air. The volumetric ratio of atmospheric gases are 78% nitrogen (N2), 20.9% oxygen (O2), 0.93% argon (Ar), 0.04% carbon dioxide (CO2), and lesser amounts of water vapor and other gases.

Oxygen is the most vital requirement for organisms that carry out aerobic respiration. To sustain life, nutrients must be converted into energy in our cells. Therefore, oxygen obtained via respiration must be carried to the cells. The amount of oxygen intake and tolerance time without oxygen varies among living things. Studies have shown that humans can live around 3 to 4 minutes without oxygen; the brain begins to shut down after 5 minutes without oxygen.

The jobs of gases during respiration

Respiration is a wonderful mechanism which is dependent on the nervous system; it is autonomous and usually takes place with ease. The respiration rate for adults is 10-15 times per minute; for children, 20-30; and for infants, 30-40. Respiration can simply be defined as the replacement of carbon dioxide gas in the blood with oxygen. Approximately 400 million alveoli in the lungs are where the oxygen and carbon dioxide exchange takes place. The oxygen that passes into the blood here is transported to cells when it binds to the hemoglobin of the red blood cells. The oxygen, which is captured by the iron (Fe) in the hemoglobin (Hb), is then released for the cells.

Roughly 4/5th of the air inhaled during respiration is nitrogen; 1/5th is oxygen. If we only need oxygen, why do we inhale other gases? It is because the integrity of air plays a critical role in breathing (the oxygen-carbon dioxide exchange). The gas ratio of air before and after respiration is given below.

As seen, while nitrogen and other gases remain constant, oxygen levels decrease, whereas carbon dioxide increases. Only 5% of the inhaled air, or oxygen, is consumed. For our cells to receive the sufficient amount of oxygen they need, the total gas pressure, composition, and oxygen concentration in the air must fit these variables. In addition, water vapor that mixes into gases inside the respiratory track assists with the regulation of gas pressure in our lungs.

The rate of gases in the air is finely tuned. If there is less oxygen in the atmosphere, aside from its many negative effects in nature, it would be insufficient for respiration; the amount of oxygen that passes into the blood to bind with hemoglobin would not be enough for our cells, and the excessive oxygen would also be toxic. For example, mountain climbers use oxygen tanks; as elevation increases, air pressure and oxygen decrease. Excessive oxygen, however, may cause loss of consciousness (coma), nausea, cramps, and visual impairment. Concentrated oxygen can be fatal for cells. According to Australian biologist Michael Denton, each extra 1% above the current 21% ratio of oxygen in the atmosphere would increase the possibility of a lighting based forest fire up to 70%.

The vital role of nitrogen

Under normal conditions, nitrogen is found in nature in its gas form as an inert element. In other words, it is created so that it only reacts under rare and special circumstances. It does not react with many substances, such as water, air, acids, and bases. Is there any function for nitrogen gas in our respiratory system?

When nitrogen gas enters our body via the air passage, it is exhaled back without getting into any reactions in our lungs, blood, or with oxygen. It does not affect the oxygen we breathe in; however, it plays a role for adjusting oxygen’s rate. Its presence is necessary for the respiration of oxygen under certain concentrations, flows, and pressure.

What would happen if any of the inert gases – like helium (He), neon (Ne), argon (Ar), or krypton (Kr) – replaced nitrogen? Not only could these gases not substitute for nitrogen with their physical and chemical features, but they could also not carry out its other functions. For instance, their solubility in blood under pressure is different. Therefore, vital problems such as decompression sickness because of different air and water pressure conditions would be seen more often, especially for pilots and divers. Also, because of different absorption and reflection rates in sunlight, our climate and other species would be affected. Furthermore, the nitrogen cycle takes part in terms of the maintenance of life on earth as outlined by natural laws.

It’s plain to see that the balance of elements and gases on our planet, and in the whole universe, have been perfectly balanced to sustain life. It seems remarkable that our planet could be created in such a way as to support so many creatures, who require such a specific balance to survive.

We tend to overlook our skin, but it performs many vital functions for our bodies – including coming to our rescue in emergencies.

Since it is designed to function within very precise limits, our body is very susceptible to small temperature changes. Since abnormalities in these changes occur, the body has various mechanisms to keep its temperature constant. One of these mechanisms works by changing the amount of blood in the veins underneath the skin. When talking about body temperature, it is important to distinguish between the internal and external body temperature. The internal temperature is the temperature of the brain and internal organs, while the external body temperature is the temperature of the skin.

Normally, arteries that transport clean blood, and veins that carry dirty blood, are not connected; therefore clean and dirty blood never mix. However, as a consequence of some illnesses or birth defects, an abnormal bridge between arteries and veins may be present. This kind of condition is usually called arteriovenous shunts, or arteriovenous fistula. In these kinds of situations, blood is pumped directly from arteries to veins. In other words, clean blood flows towards dirty blood. Normally, the clean blood has to travel the body, providing oxygen and other supplements to cells, while collecting carbon dioxide and returning to the heart to be cleaned again.

An incredible network for the transportation of substances from the blood in arteries and veins has been created. If this system, known as the “capillary network,” did not exist, none of our organs could be fed, and the circulatory system would not be able to provide its vital function.

The system is necessary for two reasons. The speed of the blood in the arteries and veins is too fast for anything to be transported to the organs, and their walls are too thick to allow transportation of substances. Therefore, the blood travels from the arteries to the capillaries, and after the trading of oxygen and other substances with carbon dioxide is completed, it flows to the veins. If any kind of abnormalities exist, the blood flows directly from the arteries to the veins, therefore skipping the capillaries. As a consequence, the organs aren’t fed and the blood gathers in the veins without fulfilling its purpose. Naturally, the oxygen and nutrition balance of the organs gets messed up. The blood is pumped out of the heart with no purpose and heart failure becomes inevitable.

The capillary network has been assigned the task of communication between arteries and veins. The skins is our only organ where the blood flows directly from arteries to veins; AV shunts accomplish a very important duty in this function.

There is a network of veins underneath the skin. The number of veins in this network is so many that if they were completely filled up, they could hold up to two liters of blood in the skin. Blood is pumped to the skin for two purposes: to provide oxygen and nutrients to the cells, and to collect carbon dioxide and waste products in the cells, as is done with every organ; and to monitor the internal temperature of the body by sending blood to the skin if the temperature gets too high, similar to what radiators in cars do when the engine gets too hot.

There is also the subcutaneous fat tissue underneath the skin which acts as an insulator. The vein network mentioned above is inside this fat tissue. There is a continuous flow of blood from the capillaries that feed the skin towards this network of veins. Moreover, especially in areas where the skin is exposed – such as the hands, feet, face and ears – there is a blood flow from the small arteries towards this network of veins. Contrary to other organs in the body, blood flows directly from the arteries to the veins. If this direct blood flow did not exist, the amount of blood in the skin’s veins would be close to zero, because the amount of blood necessary for skin nutrition is very little. However when the internal temperature rises too much, the amount of blood, which is normally close to zero, can suddenly increase to as much as 30% of the blood pumped by the heart. In this case, the body’s internal temperature is being transported to the skin. This is an incredibly efficient cooling system. However, if the weather is cold, the AV shunt veins are switched off and the skin’s blood flow is decreased until close to zero, therefore maintaining internal temperature. The fat tissue underneath the skin also has a very important function, as it acts as insulation, helping maintain temperature.

Body temperature and the body’s systems work in perfect coordination with each other. We can observe a very simplified version of this system in computer based air conditioners. However, when we reflect upon the incredibly sophisticated cooling system of the human body, we come to the conclusion that no other system is as perfect as that.

The hypothalamus, which has various vital duties for the brain, was also given the very important mission of controlling the body’s temperature. There are hot and cold heat receptors in various parts of the hypothalamus. When body temperature increases, these receptors are activated. As a consequence of this warning, skin veins all over the body expand. Simultaneous with the expansion of the veins, sweat is excreted.

The hypothalamus also has the duty of suppressing the mechanisms that produce heat throughout the body. For example, trembling is stopped and general metabolism is slowed down to decrease body temperature. As metabolism slows down, the production of heat becomes minimal, and cooling takes place. In conditions where the body temperature is too cold, some hormones secreted in the hypothalamus trigger the pituitary, and then the thyroid, hormones. Since thyroid hormones are responsible for increasing metabolism, body temperature increases. However if body temperature increases above normal, the control of the hypothalamus on the thyroid is reversed, and thyroid hormones are decreased, therefore decreasing body temperature.

There is one more reason for placing so many veins in the perfect and miraculous body’s skin: except for extremely cold weather conditions, quite a large amount of blood exists in these veins that are not used for nutritional purposes. Some of our organs act as storage for blood; two of the most important ones are the spleen and liver. Another one is the skin. In the course of losing blood, or an illness that increases the need for blood, the spleen and liver shrink. As a consequence of this shrinkage, the blood inside them is sent to the heart, through veins, and distributed to the areas in need of blood. This increases the heart rate.

A similar scenario occurs in the skin. The veins responsible for cooling shrink, and the blood they contain is sent to the heart with the help of the main veins, therefore helping the heart pump. During heavy loss of blood, the blood in the skin comes to the rescue. Patients who are losing blood have incredibly cold and pale skin. This is because the blood in the skin has reduced to a minimum.

The obverse of this happens in an illness called erythromelalgia, where more blood than normal flows from the arteries to the veins in the skin. This is mostly seen in the hands, feet, nose, and ears, since AV shunts are more prevalent in these areas of the skin. The symptom of this illness is burning pain, which is triggered by heat and soothed by cool temperatures. The nutrition of the skin decreases and some substances produced because of the absence of oxygen increases redness, heat, and pain, since some of the capillaries feeding the skin shut down and all of the blood flows from arteries to veins with the AV shunts.

Our skin protects our muscles and bones, and contributes to the beautiful aesthetic of our body. It provides our sense of touch, and is therefore a means for us to experience the material world, as well as providing temperature control for our bodies. It can clearly be seen that the relationship between the skin and the veins could not have evolved by the consequence of coincidence.