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Here are a couple of walk signs in Trafalgar Square:

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A Londoner told me that part of the country’s divide regarding Brexit was based on the fact that EU membership had made it easy for employers in London to grab up the best people from any European country experiencing an economic or political crisis. “When Spain collapsed, all of the best people in Spain were available to the banks here,” he said. “That’s been great for London, but it doesn’t help people to the north.”

The cream of the European crop is already in London (and how many more crises can Europe have?), and London has certainly run out of housing, sidewalk space, etc. So even without Brexit perhaps the city’s economic growth was due to slow?

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In anatomy, we performed a laminectomy. We removed the posterior vertebral structures to reveal the spinal cord, about the diameter of the thumb. We opened up the dura (outer meninges that forms a fibrous protective layer), a continuous white sheath that covers both spinal cord and brain. At each intervertebral level, four roots come off the spinal cord to form bilateral spinal nerves. The ventral root is where all the motor fibers exit the spinal cord to control muscles and glands. The dorsal root is where sensory fibers enter into the spinal cord. Several spinal nerves in the lumbar and cervical regions were surprisingly large, about the diameter of a pinky. How could something the size of a thumb contain nerves that occupied so many pinkies? The answer turns out to be that nerves within the spinal cord are highly myelinated, which maintains conduction speed without the need for a large diameter. Once the neurons fan out from the spinal cord, however, not all of these nerves are myelinated and therefore must be thicker. We also saw the aptly named cauda equina (horse’s tail). The spinal cord stops at L4 but the spinal nerves must exit from the lower vertebrae. The spinal nerves flow down the vertebral foramen fibers forming a horse’s tail!

This week in lecture we learned about the cerebellum (from the Latin for “little brain”) and basal ganglia. The cerebellum is located in the posterior inferior (back/lower) portion of the skull under the occipital lobe and contains an estimated 50 billion neurons in the cerebellum—more than in the entire rest of the brain and spinal cord combined! These cells can be thought of as writing computer programs to determine muscle activity and timing. One program, for example, might determine the sequence of firing hand muscles to grasp a cup. “Anyone who has had one too many cold ones knows what happens when you lose cerebellum function,” noted Doctor J. Alcohol affects the the purkinje neurons of the cerebellum first, causing the characteristic drunk stumble.

The cerebellum uses the same neural architecture to process different inputs. For example, whether information is coming from the vestibular (balance) apparatus, or coming from proprioceptive information of the big toe, the information ascends to the densely packed purkinje neurons. The purkinje cells form massive planar dendritic trees that stack together in parallel. Purkinje cells have the same branching pattern as fan coral. Information received from the nervous system is sent along parallel fibers that travel perpendicular to the purkinje dendritic trees, synapsing along the way. This allows an immense amount of connectivity.

Cerebellar lesions, for example from a stroke, are devastating. Simple tasks become near impossible as the victim has difficulty timing an action. We practiced various cerebellar tests including the finger-to-nose test where you ask patients to reach out to your finger and touch their noses. They will have an intention tremor as they near the end of the action. Doctor J commented, “Do not use their nose as the endpoint. A stroke patient will poke his/her eyes out. Use the chin.”

We had two lectures on the basal ganglia, cell bodies deep in the brain that are involved in filtering information passing through the thalamus (relay station) to the cerebral cortex. While the cerebellum’s outputs dictate the timing of muscle firings, the basal ganglia determine which muscles need to be activated. Lesions of the basal ganglia, for example Parkinson’s disease, cause debilitating rest tremors (tremors while not performing an action). We learned that stripes of tape on the floor can help Parkinson’s patients with stability. The visual cues of the tape are thought to override the abnormal baseline thalamic input. This simple addition has huge benefits for the patient and caretakers, for example, when the patient tries to get out of bed to the bathroom. “This is an easy way to help keep a Parkinson’s patient out of the hospital.”

Doctor J brought out a VHS cassette showing various tremors, reflexes, and symptoms of patients with neurological disorders. “It might be old, but it’s the best display of these symptoms.” It took two IT staff 15 minutes to get it playing. We saw symptoms and movements associated with Parkinson’s disease and Huntington’s disease. The video was apparently worthwhile; the next day, a classmate shadowing an internist diagnosed a 40-year-old patient with Parkinson’s.

Our patient case: Martha, a 62-year-old female with Parkinson’s disease accompanied by her daughter Janine. The class quickly fell in love with Martha. She was witty, humble, and kind. Martha was diagnosed about eleven years ago with Parkinson’s after presenting with balance issues, difficulty writing, and a rest tremor in her hands. The neurologist explained there are two stages of Parkinson’s. “The first stage involves movement and dexterity. Typically two decades after diagnosis, patients enter a second phase characterized by significant cognitive deterioration. There are drugs, for example carbamoyl-levodopa, that are effective at treating the tremor and movement disorders.”

Martha explained that it took a while to find the right balance. Too much of these powerful drugs can also cause tremors. She takes her medications every four hours or as needed if the tremors get worse. “If I do not take my medications, I have this terrible slowness,” explained Martha. “I want to walk but my feet do not move. They just twitch up and down with the rest of my fidgety body. My body does not respond to my mind.”

Asked to describe her typical day and what she wanted others to know about Parkinson’s, Martha responded, “Oh, I still do lots of stuff. I cannot drive, but I love to garden and cook. Everything just takes longer for me. Appreciate that it is difficult for me to get to an appointment or brunch at 10:00 am. It takes me several hours with the help of Janine to get ready.”

What was her greatest concern? She immediately responded, “That I will become dependent on Janine.” She explained that Janine was the only family member who was a significant help. A student asked Janine, “How has this changed your life?” Janine responded, “She is the center of my world. I wouldn’t change it. I wish people understood that her disease has not destroyed everything of her. There is a whole life after diagnosis. It doesn’t stop there.”

Friday afternoon, we practiced motor and reflex tests on each other. Reflexes are elicited by sudden changes in muscle length. Swinging a reflex hammer at a tendon causes a sudden increase in the length of the tendon, which sends this stretch information to reflex centers in the spinal cord. Upper motor neurons communicate with these centers for a net inhibitory effect. Therefore, an upper motor neuron lesion may result in hyper-reflexia (e.g., doctor gets hit in the nose by the patient’s foot). As we practiced on each other, two student-examinees shouted, “I got the clonus!” Clonus is when a muscle undergoes a series of involuntary contraction-relaxation cycles after a sudden change in the fiber length. The hospitalist told them not to get too excited about a few beats of clonus: “Wait until you are on the hospital wards.”

Seven students stuck around to speak to the physician. One of our classmates had suffered a stroke at age 10. He reluctantly volunteered to have his reflexes tested. We quickly identified hyper-reflexia in his left lower extremity (left leg below the knee). For the patellar reflex (knee), the leg straightened at the knee and then kept going up towards the ceiling. After that we saw more than 5 seconds of sustained clonus. This is entered on a chart as “Grade 4+” (2+ is normal). Further, the physician elicited the “Babinski sign” by moving a pen along the underside (“plantar” surface) of the classmate’s foot. His toes fanned out, which is normal for a baby under six months old. After six months, this reflex is typically eliminated as upper motor neurons suppress the primitive response. We thanked our good friend and classmate.

The next day, Doctor J held a group “question and answer” session. The class gets into six-person groups to answer challenging questions. Each group is required to hold up an answer. Doctor J would then delve into why Group 1 picked “C” whereas Group 2 erroneously picked “D”. Type-A Anita did not attend stating, “I feel humiliated when I go to these question/answer sessions and he pimps me about why I got the question wrong.”

Lunch outside with nine classmates: A woman checked CNN headlines about the missile strike on Syria on her phone and yelled that Trump was a warmonger. Type-A Anita added, “On top of this, Gorsuch was confirmed. We are going back to the Stone Ages.” The topic somehow turned to race relations. A classmate chimed in, “Ben Carson got appointed only because he is black.” A female classmate from a rural conservative family opined, “America has our class divisions but we are by far the most tolerant country compared to anywhere else.” Immediate reactions stormed in. “This is because Western culture portrays whites as heros and blacks as criminals,” a female Asian student asserted. “It is the West’s fault that other countries are not tolerant because they watch our movies and pop culture.” The discussion settled down after someone brought up the livestream of April the Giraffe (a pregnant resident of an animal park in New York).

Statistics for the week… Study: 8 hours. Sleep: 8 hours/night; Fun: 1 night. Example fun: After class, we played soccer with Ph.D. students in the rain followed by burgers and beers.

More: http://fifthchance.com/MedicalSchool2020

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Two London-based Airbus A320 captains explained the avionics in their $100 million workhorse: “Because of certification regulations, none of it has been updated since the 1980s. When you touch a button you can see the computer working to update numbers. It would be a lot better to have one iPad per side running SkyDemon.” (This would replace the navigation equipment of the Airbus; the primary flight display for attitude, airspeed, etc. would remain.)

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Anatomy lab was less than 30 minutes: we removed with blunt dissection the posterior muscles around the vertebral column to prepare for next week’s laminectomy (removal of the vertebral laminae to expose the spinal cord)! We went over spine anatomy and common spine disorders such as a herniated (“slipped”) disk (the gelatinous nucleus pulposus part of the intervertebral disk herniates through the outer fibrocartilage annulus fibrosus) and spondylolisthesis (anterior or posterior displacement of a vertebra). We discussed how aging causes loss of the elastic dampening capabilities of the nucleus pulposus.

Lectures detailed two sensory systems, the anterolateral and medial lemniscal tracts. The anterolateral tract conveys tissue damage (pain), whereas the medial lemniscal tract conveys fine touch and proprioception (vibration and positional awareness). Sensing vibration requires extremely responsive transducer elements in the skin to convert rapid changes in pressure into electrical signals. All these tracts end in the postcentral gyrus in the cerebrum, which forms the sensory homunculus. The medial part receives sensory input from the lower extremity. The genitalia neurons are adjacent to the foot neurons, a potential explanation for why some humans have a foot fetish. The lateral part of the brain receives sensory input from the upper extremities.

Doctor J called the tallest student up to the front. He grabbed a measuring tape and asked the student to step on one end of it. He then measured all the way up his back to the end of his neck — 5’6. “This is the length of a single neuron in your body.” The whole class was amazed. Neurons that sense fine touch and proprioception travel from the big toe up to the spinal cord, ascend the spinal cord in large bundles, and finally synapse in the medulla (part of the brainstem). One cell.

Our patient case: Sherry, a 50-year-old overweight female accountant with uncontrolled diabetes presents to her primary care physician with a foot ulcer. During tax season she is so busy that she forgets to take care of herself. She has not refilled her medications, including metformin, for several months. A neuromuscular exam, specifically using a 256 Hz tuning fork to test for vibration sensitivity, reveals diminished sensory ability in both extremities. She explains that her foot has felt numb for weeks. A cut on the foot went unnoticed, and got infected.

Sherry suffers from diabetic peripheral neuropathy. Uncontrolled glucose levels lead to non-enzymatic glycosylation (adding sugar groups) of proteins,lipids, and nucleic acids. These advanced-glycosylated products (AGEs) interfere with normal function and activate inflammatory pathways. A familiar complication of diabetes is vascular (arteries and veins) damage, which leads to increased risk of atherosclerosis, heart attack, and stroke. This inflammation also damages neurons and their companion Schwann cells (cells that myelinate peripheral nervous system axons). The longest axons are affected first. The neurological deficits such as numbness, loss of pain sensation and balance difficulty start in the foot and travel up the leg. By mid-calf, the sensation loss also begins in the hands. Fifty percent of diabetics have peripheral neuropathy (eighty percent after 15 years). Interestingly, the physician mentioned that twenty percent of prediabetics have some sign of developing nerve damage, suggesting that vibration tests should be used as a screening tool for diabetes.

Sherry had trouble simply walking. As is common among laypeople, classmates associate diabetes with laziness: failure to exercise, overeating. This case prompted us to ask “How could someone exercise if they cannot walk?” The physician concluded, “It is critical for diabetics to check their feet daily. They might not even realize they have a cut or foot ulcer. The infection can spread to the bone requiring hospitalization and, too commonly, amputation.” He reminded us that diabetes is the leading cause of amputations [73,000 in 2010]. Sherry described her diabetic foot ulcer, now cured, as a wake-up call. She was discharged from the hospital three months ago and has been taking her medications regularly.

A diagnostic radiologist and an interventional radiologist led a lunch session about their respective specialities. Diagnostic radiologists complete 5 years of training: an internship year typically on general surgery followed by a 4-year radiology residency. Interventional radiologists conventionally would complete a separate 2-year interventional radiology (IR) fellowship, making for a total of 7 years of post-MD training. There are now direct IR residencies that take just 5-6 years.

IR is a subspecialty of radiology. Interventional Radiologists perform minimally-invasive procedures using imaging guidance such as x-ray and ultrasound. These procedures include: central line placement, endovascular (e.g., stents and thrombectomy of blood clots) procedures, radiation treatment, and bile duct obstruction procedures. Other specialities overlap with many of these. Indeed, there is sometimes tension what specialty group performs a given procedure at different health systems. For example, stents can be placed by IR or interventional cardiology; strokes can be treated by neurosurgery or IR.

The interventional radiologist explained why he chose IR: “I loved anatomy. And I like working with my hands doing procedures.” The diagnostic radiologist explained why she choose radiology: “I had the worst internal medicine rotation fourth-year. Day after day, I would have a patient die on me. The worst was a 30-year-old cystic fibrosis patient, the exact same age I was. I was so miserable I considered quitting medical school or not completing a residency. A radiologist lived upstairs of me and noticed how miserable I was. He suggested I shadow radiology. Never looked back.”

She described radiology as the “experts’ expert.” Clinicians increasingly rely on imaging procedures as opposed to physical examination skills. “Do not go into radiology if you cannot wield responsibility. You decide if someone in the ED goes to the OR or gets sent home.” We learned that radiologists are highly compensated, but also have a higher liability profile: “Every radiologist will be sued several times.”

What will the role of machine learning play in radiology? “Computers will not replace radiologists. They will just make radiologists much better at their jobs.” The diagnostic radiologist elaborated, “Computer algorithms in some areas are just as good as radiologists in identifying if something is wrong with a patient [high sensitivity]. However, computers are terrible at ruling out issues [low specificity].” I attended a neurosurgery informal dinner where I asked a similar question about radiology. The neurosurgeon was shocked by the radiologist’s response, and exclaimed, “Radiologists are terrible at ruling things out. Every report is littered with: ‘cannot rule out x, y, or z’. Give me a break, they will be replaced.” (See “A.I. Versus M.D.,” New Yorker, April 3, 2017.)

I’ve been working on a personal project in the evenings. My favorite trauma surgeon comes in most Wednesdays at noon to evaluate my progress. She tidies up my dissection then sends me on another mission that our class did not have time to explore during formal anatomy lab. Examples: Find the annular ligament of the radius, the ulnar nerve, or the anterior humeral circumflex arteries. One thing that makes medical school different is that an after-hours project may involve a dead body. In this case, I have a whole cadaver to myself, unlike in anatomy lab where we switch bodies every few months. The cadaver was a black 60-year-old, mildly overweight female. I have developed a deep sense of appreciation for this woman who donated her body so that I could pursue this upper extremity (arms) project focused on nerve and blood vessel anatomy.

One evening around 9:30 pm there was a knock on the locked door. I took off my soaked gloves and opened the door to find the head dean escorting a fundraiser group of dressed-up bankers and business people. They wanted to see the wet lab. I forgot how quickly one adjusts to the sight of cadavers in a formaldehyde-scented room. As I was there by myself, the whole head was uncovered and several chunks of removed fat lay exposed. A few people approached the body, but most were hesitant and stayed at least several feet away. I showed them the nerves and vessels of the arm.

A visitor asked about the purpose of cadavers. I explained that cadavers give unparalleled understanding of human anatomy. Textbooks cannot replicate this experience, especially the geometric relations of anatomical structures. An important part of the learning experience is discovering how the individual died and what diseases he or she lived with. I mentioned that one cadaver had a heart attack, prompting a question from a gentleman in his late 50s regarding what the heart looks like after a heart attack. I explained the cadaver suffered a heart attack in his left anterior descending (LAD) artery, as evidenced by a small, hardened discoloration on the surface of his left ventricle (see previous post). He did not die from the myocardial infarction because hardened scar tissue replaced the infarcted region. If he did die from the MI, the infarcted region would have the same firmness as the rest of the myocardium. The gentleman thanked me, took a peek at the cadaver and left. The next day the dean told me that the wet lab had been the guests’ favorite part of the event.

Statistics for the week… Study: 8 hours. Sleep: 6 hours/night; Fun: 1 nights. Example fun: Two classmates and I attended this year’s SonoSlam in Orlando, Florida. SonoSlam is an ultrasound competition among medical schools held on a Saturday by the American Institute of Ultrasound in Medicine (AIUM). My favorite part was using the most advanced ultrasound machines. Several of machines were controlled via iPads. One bluetooth-enabled ultrasound probe was only slightly larger than a smartphone and could be controlled via an iPhone app. The competition ended around 6:00 pm. As first-year students without the pathology training of the fourth years, we had low expectations for the competition and we did not exceed them. However, we celebrated our failure with post-competition drinks at a local brewery and “Cutthroat” at a nearby billiards parlor.

More: http://fifthchance.com/MedicalSchool2020

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Now that we’re sufficiently distant from the obligatory sentimentality around Mother’s Day, let’s look at Sheryl Sandberg’s Facebook posting on the subject:

Being a mother is the most rewarding – and hardest – job many of us will ever have. The day you become a mom, you also become a caregiver, teacher, nurse, and coach. It’s an all-in-one kind of role that comes with no training.

Apparently she and Bill Burr are destined to disagree regarding the difficulty of a job that can be done in pajamas.

For most moms, it’s only one of many jobs we have. Over 40% of mothers are the primary breadwinners for their families – and in many, the only breadwinner. We all have a responsibility to help mothers as well as fathers balance their responsibilities at work and home.

Celebrating the heroism of single mothers is a stock item for politicians so perhaps Sandberg will soon run for office? But can she be right about a significant number of single moms being the only breadwinner? If this is a low-income mating situation, the taxpayer will be providing the single mom and her children with a subsidized (or free) house, free health care, and free food. If this is a high-income mating situation, the child support defendant will be sending a stream of cash into the mother’s checking account.

Companies can do a lot to lead the charge, and I’m proud of the steps Facebook has taken. But not everyone has the opportunity to work for a company that supports working parents. It’s time for our public policies to catch up with what our families deserve and our values demand.

To start, it’s long past time to raise the federal minimum wage. Two-thirds of minimum wage workers are women. Raising the wage would reduce pay inequality and help millions of families living in or near poverty.

Sandberg is concerned about “pay inequality.” Her reported net worth is $1.6 billion. Thus we can estimate that she has been paid $2-3 billion pre-tax by Facebook, money (or the stock equivalent) that otherwise could have been paid to employees lower down in the bureaucracy. Why not reduce pay inequality at Facebook before asking for government intervention in the labor market for other employers (let’s assume that Facebook, being in Silicon Valley, is forced by the market to pay well above the minimum wage, so a change to this law will have no effect on Sandberg’s personal wealth).

We need paid leave. The United States is one of the only developed countries in the world that doesn’t guarantee paid family leave – and we’re the only developed country in the world without paid maternity leave. That means many moms are forced to return to work right after giving birth to keep their jobs. They deserve more support. So do dads, LGBTQ parents, adoptive parents — families of all kinds.

So those Americans who haven’t been fortunate enough to find a mate or have a child are going to be further disadvantaged by a forcible transfer of income to those who have been blessed with a mate (at least for a few hours) and children?

All of us will have times when we need to take care of ourselves and our relatives. We shouldn’t have to risk losing a job or being able to meet the basic needs of our families to do that.

And we need affordable child care. Child care for two children exceeds the median annual rent in all 50 states. How are parents supposed to work if they don’t have a safe and affordable place to leave their kids?

More wealth transfer from the childless will be required!

On this Mother’s Day, even more than ever, I feel deep gratitude for my amazing mom Adele Sandberg, who has given me her love and strength my whole life and these past two years especially. I am also grateful for the love and support of my mother-in-law Paula Goldberg who dedicates herself not only to her own family, but to families with children with disabilities through the PACER Center. For those for whom this day can be more painful than celebratory, I hope – as Connie Schultz would say – that it lands gently.
This is an emotional day for so many reasons – because we thank the mothers we have and remember the mothers and the children we’ve lost. I hope we can also use this day to commit to do more for all the mothers who have given so much and deserve even more.

Sandberg proposes to hit women who couldn’t find a mate and/or couldn’t have a child with higher tax rates to subsidize their sisters who were fortunate enough to become mothers. But Sandberg offers them some kind words in exchange for their higher tax payments!

Related:

• The inquisitive gender studies student and Sheryl Sandberg
• Sheryl Sandberg sweeps away sex discrimination at Facebook
• Sheryl Sandberg: Everyone is stupid compared to me
• Sheryl Sandberg: thinking small
• Sheryl Sandberg, Jane Austen, and the Queen of Versailles
• Lean In
• Lean In: Women can move up the career ladder as soon as men change

 

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From our anonymous insider…

We had a week off. Several classmates visited girlfriends, boyfriends, and family. One went on a Caribbean cruise. A few stayed in town to recuperate and study this next block in advance (“gunners” is the class label for this behavior).

We’ll study neurology for the next two months, but class began with two deans reprimanding us. “It has come to our attention that several doctors and professors think you need to work on professionalism. Several of you are on Facebook, browsing Amazon, and checking Instagram during lecture while you sit next to a physician. SnapChatting in class is inexcusable. These physicians frequently volunteer their time to come in and speak to you. Treat them with respect. Every class gets a reputation. Don’t let this be yours.”

For eight weeks we will be taught almost exclusively by a 74-year-old neuroanatomist, “Doctor J”. He worked for several years as a physical therapist, then earned a Ph.D. in neuroscience. His first slide was a quote from Emerson Pugh: “‘If the human brain were so simple that we could understand it, we would be so simple that we couldn’t.” “We will do our best,” explained Doctor J. His second slide was a black and white photo of an old guy. “Neuroscientists bow before Cajal.” In the late 1800s there was no consensus on the anatomy of the nervous system. Two luminary anatomists, Camillo Golgi and Santiago Ramón y Cajal, supported opposing viewpoints. Golgi supported the reticular theory: nerves are a syncytium of several cells connected together. Cajal supported the neuron theory: each nerve is a single cell. Cajal used Golgi’s own staining method to disprove the reticular theory. This history lesson gave a human spin to the evolution of knowledge. These men worked in shoddy laboratories with microscopes that we could build today out of paper and tape.

We had to purchase several tools for the neurological exam, including a reflex hammer, pen light, and eye chart. Our white coat is filling up with gadgets! We will practice the exam in several workshops. Students complained to the dean about Doctor J not posting answers to the workshop questions. The neuroanatomist responded during lecture, “This is your fault. The first few years we did give out answers for the lab book. I put a copy in the library. Within a week, someone had photocopied it and send it as PDF to the whole class. The value of the workshops went down, no one attended, so I no longer give the answers out.” Apparently not all classmates were mollified by this explanation because enough students went back to the dean that he submitted a “formal grievance” against Doctor J.

Lecture began with an overview of the nervous system, divided into a central nervous system (CNS) and peripheral nervous system (PNS). The CNS is a tube with a hollow canal in the middle where cerebrospinal fluid flows. This tube is simple in the spinal cord but becomes suddenly more complicated at the top of the tube, which will become the brain. During fetal development (in utero), the cells of this part grow much faster than the surrounding skull causing bending and folding of the tube. The brain retains its lumen (inner membrane adjacent to canal) as the four ventricles of the brain that are continuous with the central canal of the spinal cord.

Unbeknownst to me, the spinal cord does not extend the whole length of the spine. Before birth, the spinal cord extends to each vertebrae. However, during childhood the vertebrae elongate faster than the the spinal cord, resulting in the spinal cord’s termination at the first or second lumbar vertebrae (above the hip bones). A lumbar puncture (“spinal tap”), a common procedure to sample cerebrospinal fluid, leverages this anatomy by sampling the cerebrospinal fluid at L4 without the risk of puncturing the spinal cord.

There are about 860 billion cells in the brain, only 10 percent of which are neurons. Ninety percent are supporting cells called glia and microglia. These cells perform various functions: astrocytes (a type of glia) maintain the blood-brain barrier by wrapping foot processes around ninety-five percent of the capillary surface area (it reminds me of the scintillating podocytes in the glomerulus of the kidney); oligodendrocytes (a type of glia) insulate the axon cable (wire to the next neuron(s)) by wrapping sheaths of their cytoplasm around the cable; microglia are specialized resident macrophages that get in the central nervous system in utero before the blood brain barrier is formed.

Myelination is essential for neuron function. The conduction velocity of the action potential (the nerve signal) decreases as the resistance of the axon cable increases. Organisms such as the giant squid without myelinating cells achieve high transmission speeds by having huge axon diameters. Myelination decreases the effective membrane capacitance, which reduces the amount of potential needed to charge up the axon, and decreases potential leakage. Myelination enables the preservation of high speed as more neuron connections are packed into a small volume. This is important because intelligence is related to the connectivity (or synapse density) of each neuron. A human brain is estimated to contain more than 100 trillion synapses for roughly 86 billion neurons.

We learned how the number of cells change during human development. Between the third week and twenty-eighth week after fertilization, 250,000 brain cells are produced every minute! Many of these neurons undergo apoptosis (cell suicide) during training of the neural network. Despite this amazing proliferation, the brain is only twenty-five percent of its adult size at birth; the brain reaches seventy-five percent of its adult size at one-year of age.

In my small group we discussed foundational neuroanatomy structures. The corpus callosum is a bridge for nerve fibers to cross between cerebral hemispheres. Someone mentioned the corpus callosum is thicker in females. A question “Is this why women are more emotional?” yielded chuckles from several male students and glares from Type-A Anita and straight-shooter Sally. Anita replied, “Yes, that is exactly why. It’s going to be a long two months with you guys.”

Anatomy held a dry lab in which we felt bone vertebrae. Dry vertebrae (just the bones) have spinous processes which look like something out of a Game of Thrones episode. The spikes you can feel on your back are these spinous processes. The vertebral body, the main weight-bearing part, lies deep to this on the anterior (front) side. The spinal cord sits between the vertebral body and the spinous process inside the vertebral foramen (hole). The spinal cord gives off spinal nerves through the small bilateral intervertebral foramen. We saw how the intervertebral facet joints differ among the cervical, thoracic, and lumbar (neck, chest, and lower back) regions. The cervical vertebrae have the joints in the axial (horizontal) plane facilitating rotation; the cervical have the joints in an oblique plane preventing significant movement here; and, the lumbar vertebrae have their joints in the sagittal (vertical side section) facilitating forward bending and extension.

Our patient case: Jonathan, 25-year-old male presents to the ED nine months ago for a three-minute seizure and worsening headaches in the morning for the past month. A neurological exam shows absence of venous pulsations, suggesting elevated intracranial pressure. Jonathan did not pay much attention to the headaches. He was busy at work, and his wife was due with a second child.

A CT (“CAT scan”) revealed a 3x3x3 cm (a little more than a cubic inch) tumor in the right temporal lobe of the brain. Surgery was scheduled immediately. The neurosurgery team debated removing the entire temporal lobe or just a “lesionectomy” where they remove the tumor with as good margins as possible. A lesionectomy was performed and a pathology analysis of some of the tumor removed revealed a grade III glioma. Jonathan’s neurosurgeon told us that “All grade III gliomas eventually become grade IV.” A death sentence. Jonathan is still alive, nine months after his first ED visit, but was unable to attend due to worsening health.

According to the neurosurgeon, a patient presenting to the ED with a headache will always get a head CT. However, it is unlikely the same patient’s primary care doctor will order a head CT for just a headache.

How many patients with advanced brain cancer elect not to get surgery? “Much more rare than you would expect,” responded the neurosurgeon. “Everyone hopes they will be the exception, the extreme outcome. We hope for a cure, so our treatment plan is very aggressive.” He has operated on a 86-year-old with grade IV glioma (the patient died; Medicare paid the bill). He recounted a troubling story of a 60-year-old late stage Huntington’s patient with glioblastoma. “His wife had a very difficult time letting go. We said we could get him back to baseline, but that baseline was late stage Huntington’s. They decided to not operate.”

What’s more important for neurosurgery, dexterity or knowledge? “We can teach a monkey to do surgery in seven years. Passion is the most important quality. I see senior residents get angry at newer residents because they work shorter hours than they did. They are bitter, and remorseful. Unless you have the passion, you will burn out.” He joked that sometimes beginners can be too passionate. “One of my residents got so excited about a successful shunt [apparently, a common neurosurgery procedure] he performed. It’s not that big a deal, we do shunts every damn day. I did not want to burst his bubble so I told him ‘Great job!’… Don’t tell him I said that!”

How did he cope with such depressing cases? “It is tough. I see cases like Jonathan’s every month,” he answered. “Everyone manages it differently. For me, as long as I feel like I treated my patient and their family like my family, I sleep fine. It is when I remember at night that I forgot to talk to that family member that it hits me.”

A seventy-year-old dermatologist with a strong southern accent held a lunch session to explain why his field is the best: “I cannot think of a single reason why you would not want to do Derm. It pays well. It has unbeatable hours. The patient population is generally quite motivated to get better.” He was in private solo practice for much of his career. “Many of my patients, such as lawyers, paid cash.” A classmate asked, “Did it get lonely working solo?” He responded, “No, we have nurses.” He described how there are just not many dermatologists, claiming this was the reason why there were so few dermatology residency slots. Dermatology is one of the most competitive residency programs.

Friday was Match Day, a slight misnomer because it is one day after fourth-year medical students hear where they will (or will not) be completing residency. Students and residency programs rank their top choices. Almost 36,000 domestic medical students and international doctors vied for about 29,000 residency slots. Fifty percent of applicants nationwide got their first choice.

The whole school attends the ceremony. Each student goes up to the podium and says something like “I will be will doing Internal Medicine at the University of Southern California.” Fifteen percent of the class couples matched. Two individuals need not be married or in the same specialty to couples match. An orthopedic surgeon sent an email out congratulating the class on their impressive Match Day results, but reminded the first through third year students not to slack off. He ended with a quote from Will Rogers: ” Even if you are on the right track, you will get run over if you just stand there.”

Statistics for the week… Study: 10 hours. Sleep: 7 hours/night; Fun: 2 nights. Example fun: A good friend and former coworker visited for the weekend. We joined Match Day celebration at a pregame followed by a late bar night filled with plenty of Guinness for Saint Patrick’s Day. Jane and I saw Beauty and the Beast on

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Right next to my hotel…

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In some meetings in London regarding the helicopter market I noticed a big difference in how pleasant well-educated natives spoke about the people who might want to go from Point A to Point B within this cloud-plagued rain-soaked traffic-clogged land. Where an American might have said “executives” or “businesspeople,” the British consistently referred to potential helicopter users as “businessmen.” Nobody seemed surprise by this phrase, not even the female consultants at the global management consultancy conducting the meetings.

Readers: Is this just another example of the persistent inability of people in England to use the English language correctly? Or does the apparent sexism of the language reflect a society that is in fact more sexist than the U.S.?

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Mark Zuckerberg showed up this year to give the commencement speech at Harvard. Let’s look at parts of the transcript:

graduates of the greatest university in the world

What better proof of the high quality of a university than that the most successful affiliates are those who dropped out? (See also Bill Gates, apparently too busy saving Africans (or “sharing the load” of housekeeping with his wife?) to give this year’s address.) Times Higher Education gives Harvard a solid #6 ranking, behind such schools as Oxford, Stanford, and Cambridge.

my best memory from Harvard was meeting Priscilla. But without Facemash I wouldn’t have met Priscilla, and she’s the most important person in my life

She faces some obstacles to becoming the most important plaintiff in Zuckerberg’s life, though, because the wedding was deferred until a day after the IPO (see “Zuckerberg’s post-IPO wedding is smart legal move” (Reuters) and our chapter on California family law).

Many of our parents had stable jobs throughout their careers. Now we’re all entrepreneurial, whether we’re starting projects or finding or role. And that’s great. Our culture of entrepreneurship is how we create so much progress.

Young people are better and more interesting than their boring parents. The Harvard graduate who goes to work for the government is an “entrepreneur.”

Millennials are already one of the most charitable generations in history. In one year, three of four US millennials made a donation and seven out of ten raised money for charity.

[Entrepreneur notes that “Despite being the largest U.S. demographic by age, the generation of 18-to-34 year-olds donates less and volunteers less for charitable causes than any other age group.” “Why Are Americans Less Charitable Than They Used to Be?” (Atlantic) says “The average American has grown more tight-fisted in recent years, donating a smaller portion of his or her income to charity than he or she did 10 years ago.” (Of course, the authors note that high-income Americans have become less charitable recently, but don’t consider the possibility that this could be due to higher tax rates, such as the Obamacare tax on investment income.)]

giving everyone the freedom to pursue purpose isn’t free. People like me should pay for it. Many of you will do well and you should too.

[… on average not as well as folks who chose to become California prison guards.]

We should have a society that measures progress not just by economic metrics like GDP, but by how many of us have a role we find meaningful.

Maybe Facebook can re-hire Chia Hong to measure the meaningfulness of jobs within the company? (See also “Underpaid and overburdened: the life of a Facebook moderator” (Guardian))

We should explore ideas like universal basic income to give everyone a cushion to try new things. … In a survey asking millennials around the world what defines our identity, the most popular answer wasn’t nationality, religion or ethnicity, it was “citizen of the world”. That’s a big deal. Every generation expands the circle of people we consider “one of us.” For us, it now encompasses the entire world.

UBI will enable everyone to start a company. Certainly no American would use his or her UBI to become an opiate addict, as has been common with SSDI and Medicaid.

[If you’re a citizen of the world and also support universal basic income (UBI), shouldn’t everyone on the planet get a handout? Why does someone who happens to be physically in the U.S. have a greater entitlement than a fellow citizen of the world in Bolivia, India, or China? We take the total wealth we’re going to hand out and divide by 7.5 billion? Or do we exclude citizens of the world who live in the richer-than-the-US countries from joining the check-of-the-month club?]

We’re going to change jobs many times, so we need affordable child care to get to work

Guy with a kid says that people with no kids should work harder and pay higher taxes to subsidize his child care costs.

We get that our greatest opportunities are now global—we can be the generation that ends poverty, that ends disease. … How about curing all diseases and asking volunteers to track their health data and share their genomes? Today we spend 50x more treating people who are sick than we spend finding cures so people don’t get sick in the first place.

There is no way that viruses will turn out to be smarter than humans. Certainly throwing money at a problem will solve it. Maybe a War on Cancer instead of these ongoing battles we’ve been funding?

How about stopping climate change before we destroy the planet

There is no better way to conserve the planet’s resources than tearing down four houses and rebuilding them in the same location.

Readers: What struck you about the dropout’s speech to the graduates?

Related:

• Christmas love from New Yorker magazine to Mark Zuckerberg, philanthropist
• Is the new Zuckerberg fake charity an estate tax avoidance scheme?
• Can a school system that wastes $1 billion per year waste another $200 million?
• More from Chaos Monkeys

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