a version of which I've taught almost every year for the last

twenty years and it evolves a little bit every year.

I think I get a little bit better at it,

so hopefully you'll get some advantage from that experience.

But the idea is to try to present to you what's exciting

about Biomedical Engineering, the ways that one can take

science and mathematics and apply that to improve human

health. I'm not working alone here,

but we have three teaching fellows who are affiliated with

the course, two of which are here today.

Yen Cu is back there, Yen raise your hand higher so

everyone can see. Yen worked on the course last

year and she's the senior of the teaching fellows that are

working on the course this year. Serge Kobsa is in the back and

he'll be the second teaching fellow.

I should mention that Yen is a PhD student in Biomedical

Engineering and Serge is an M.D./PhD student who's getting

his PhD in Biomedical Engineering.

The third teaching fellow couldn't make it today,

his name is Michael Look and I'll introduce him to you when

he's available. This is the goal for my

first lecture today, to try to answer these

questions. You might have already noticed

that I'm using the classes V2 server so the syllabus is there,

I'm going to go over the syllabus a little bit later,

but the syllabus is available online.

The first reading is available online and I'll talk more about

the readings when I get to that portion of the lecture here.

I'm going to post PowerPoints for all the lectures,

hopefully at least the day before the lecture takes place,

so I posted this last night. Some students find that they

benefit from printing out the PowerPoints and they can just

take their notes along with the slides as I go and that's one

way to do it, but feel free to do it whatever

way works for you, but those should be available.

The questions I want to try to answer today are what is

Biomedical Engineering? So why would you be interested

in spending a semester learning about this subject?

I'll talk about who will benefit from the course and a

little bit about sort of the detailed subject matter that

we'll cover in the course of this semester.

To answer the question what is Biomedical Engineering,

we're going to spend time on that today and we'll spend time

on Thursday, and I want to approach it from

a couple of different angles. One is by just showing you

a series of pictures which you might recognize and talk about

why this is an example of Biomedical Engineering.

This is one picture that probably you all know what it is

when you see it, it's a familiar looking image.

It's something that probably we all have some personal

experience with, right?

This is a chest x-ray that would be taken in your doctor's

office, for example, or a radiologist's office.

And it is a good example of Biomedical Engineering and that

it takes a physical principle, that is how do x-rays interact

with the tissues of your body, and it uses that physics,

that physical principle to develop a picture of what's

inside your body, so to look inside and see

things that you couldn't see without this device.

And you'll recognize some of the parts of the image,

you can see the ribcage here, the bones, you can see the

heart is this large bright object down here.

If your - have good eyesight from the distance that you're at

you can see the vessels leading out of the heart and into the

lungs, and the lungs are these darker

spaces within the ribcage. Physicians over the years

of having this instrument have learned how to be very

sophisticated about looking at these pictures and diagnosing

when something is wrong inside the chest,

for example. So this is an example of

Biomedical Engineering, one that is well integrated

into our society to the point that we've probably all got a

picture like this somewhere in our past,

and where we understand the physical principles that allow

us to use it. We've gotten,

over the last two decades in particular, very sophisticated

about taking pictures inside the body allowing doctors to look

inside the body and predict things about our internal

physiology that they couldn't predict just by looking at us or

putting their hands on us. This image on the top here is

another example of an imaging technique, this is a Positron

Emission Tomograph, or PET image,

and it's taken by using radionuclides and injecting them

into you, so radioactive chemicals that

interact with tissues in your body in a specific way and you

can where those radioactive chemicals go.

It allows us to look not just at the anatomy of what's going

on inside your body like an x-ray does,

but to look at the chemistry, the biochemistry of what's

happening inside a particular organ or tissue in your body.

In this case, these are pictures of the brain

and this has been an exceptionally important

technique in understanding how molecules like neurotransmitters

affect disease and how they change in certain disease states

in people, and we'll talk about this as

another example of Biomedical Engineering, this advanced

method is for imaging inside the body.

Well this third picture you can't probably see too much

about but you probably recognize what it is, right?

Where was this picture taken? What kind of a space was it

taken in?

Student: [inaudible]Professor

Mark Saltzman: Somebody said OR or

operating room and that's right, this is a picture in an

operating room, and operating rooms if you went

into any operating room around the country you would see lots

of examples of instruments that are used to help surgeons,

anesthesiologists to keep the patient alive and healthy during

the course of a surgery. This particular one down

here, this portion here is a heart/lung machine and this is a

machine that can take over the function of a patient's heart

and lungs during the period when they're undergoing open heart

surgery, for example.

If they're having a coronary artery bypass or they're having

a heart transplant, then there's some period at

which their normal heart - their heart is stopped and this

machine assumes the functions of their heart.

And this is, I think, an obvious example of

Biomedical Engineering, building a machine that can

replace the function of one of your organs even temporarily,

for example, during an operation.

This is another familiar picture, I purposely picked one

that looked sort of old fashioned compared to the usual

way you see this, which might be on the nightly

news. You see a bleep going across

the screen to indicate that they've got their finger on the

pulse of what's happening, or you see it in TV shows like

ER. You see these images on

computer screens all the time; it's an example of an EKG or

ECG, an electrocardiograph. It's a machine that also looks

inside your body, but looks inside in a different

kind of way. Rather than by forming an image

or a picture you put electrodes on the surface of the body and

measure the electrical potential as a function of position on the

body. It turns out the electrical

potential or electricity that you can measure on the surface

of the body reflects things that are happening deeper inside like

the beating of your heart. If you put the electrodes in

the right position and you measure in the right way you can

detect the electrical activity of the heart and record it on a

strip recorder like this one shown here,

or display it on a computer. So this is another example of

Biomedical Engineering where you can look at the function of a

heart in a living person and a physician who is experienced at

looking at these, and a machine that works well,

with those two things you can diagnose a lot of things that

are happening inside of a heart and we'll talk about that about

halfway through the course. This picture might be less

familiar to you but you probably all know that we have developed

over the last 100 years or so the ability to take cells out of

a person, or cells out of an animal,

and keep those isolated cells alive in culture for extended

periods of time: this technology is called cell

culture technology. We're going to spend quite of

bit of time talking about it during the third week of the

course. By taking cells from the skin,

for example, or cells from your blood or

cells from the bone marrow and keeping them alive in culture,

we've been able to study how human cells work and learn a lot

about the functioning of human organism.

We've also learned how to not only keep cells alive,

but in certain cases make them replicate outside the body,

so maybe you could take a few skin cells and keep them in

culture in the right way and replicate them so that you get

many millions of skin cells after several weeks or so.

Now one of the new technologies that's evolving,

that we're going to talk about in the last half of the course,

is taking cells that have been propagated in this way outside

the body and encouraging them to form new tissues.

This is one example of that: this is actually artificial

skin. It's in this Petri dish.

Here is a thin membrane, it's a polymer scaffold,

and on that polymer scaffold scientists have placed some skin

cells and they've allowed it to grow.

And if you maintained it in the right way, this polymer scaffold

together with the skin cells will grow into skin.

And you can use this tissue engineered skin to treat a

patient who's had severe burns, for example,

or a diabetic who's developed ulcers that won't heal.

So this is an example of a technology that's just emerging

now, it's certainly going to impact you in your lifetime and

we'll talk about how it works and what the current

state-of-the-art is there. This device held here is

really made of mainly plastic and a little bit of metal.

It's a fully implantable artificial heart,

and it was introduced about seven or eight years ago now.

It was implanted into the first patient, a gentleman in

Kentucky, and he stayed alive for a period of time with this

device replacing his heart. Development of an artificial

heart, again another example of Biomedical Engineering,

is something that people have been trying to accomplish for

decades now, and this is the closest that we've come and

there are many advantages of this particular artificial

heart. And it's important innovation

in several different ways and we're going to talk about this

whole science of building artificial organs,

devices that are made out of totally synthetic components to

replace the function of your natural organs,

and the artificial heart is a good example of that.

This picture on the bottom here is really just a series of

colored dots. Some are yellow,

some are red, and some are green - does

anybody know what this is? Have you seen pictures like

this? It's an example of a technology

called a gene chip that allows you to, on each one of these

spots there is DNA for example, that's specific for a

particular gene in your genome, in the human genome for

example. By incubating a small sample of

fluid from a patient on a gene chip like this,

where every one of these dots represents a different gene,

you can see by looking at the pattern of colors on this chip

which genes are being expressed and which genes are not being

expressed in that particular individual.

So it lets you do a profile of not just the genes that you

possess, for example, but what genes are actually

being used to make proteins in the cells that surround the

fluid where this was collected. So this has been a remarkable

innovation. It's another example of

Biomedical Engineering technology that allows us to

look at what's happening inside an individual,

a patient, in a totally different way than we were

before. By looking to see not just what