Artificial Organs:


THE FDA INITIATES 3 ARTIFICIAL
KIDNEY PROGRAMS
In April 2012 three products for
patients with end stage renal disease
(ESRD) have been chosen to
participate in the FDA’s Innovation
Pathway, an evolving system designed
to help develop  medical devices.

The FDA selected three from 32
product applications ranging from an
artificial kidney to devices that assist
kidney function.

The three products are:

  • An implantable Renal Assist
    Device (iRAD) being developed
    by the University of California,
    San Francisco.
  • A Wearable Artificial Kidney
    (WAK) in development by Blood
    Purification Technologies Inc. of
    Beverly Hills, Calif.
  • A Hemoaccess Valve System
    (HVS) that has been designed
    by Greenville, S.C.-based
    CreatiVasc Medical.

ESRD is the progressive loss in kidney
function over a period of months or
years. The kidneys play an essential
role, filtering and removing waste from
the body and producing hormones that
are responsible for calcium absorption
and red blood cell production.

The FDA chose ESRD because more
than half a million Americans suffer
from the disease. Management of the
disease is largely dependent upon
medical device technology, such as
hemodialysis (process for removing
waste products) equipment. Most
dialysis patients spend long hours in
specialized outpatient clinics, impacting
their quality of life and reducing
productivity. Medicare alone covers
some 75 percent of ESRD health care
costs, which in 2009 topped $29 billion.

The UCSF artificial kidney, or
implantable Renal Assist Device
(iRAD) would include thousands of
microscopic filters as well as a
bioreactor to mimic the metabolic and
water-balancing roles of a real kidney.

The combined treatment has been
proven to work for the sickest patients
using a room-sized external model
developed by a team member at the
University of Michigan.The goal is to
apply silicon fabrication technology,
along with specially engineered
compartments for live kidney cells, to
shrink that large-scale technology into
a device the size of a coffee cup. The
device would then be implanted in the
body, allowing the patient to live a
more normal life.




LUNG CANCER: ARTIFICIAL AIRWAY
IS A WORLD FIRST
French doctors said that at a medical
first  a 78-year-old man was given a
section of artificial airway to save a
lung afflicted by bronchial cancer.
The bronchi are the main tubes for
taking air from the trachea to the two
sides of the lung.

In cases of early, non-metastasizing
cancer of the bronchus, surgeons
typically remove a whole lung, as well
as the bronchus itself, if the tumor is
located in the centre of the organ.

In more than a quarter of cases, this
leads to death within three months of
the operation.

A team led by  surgeon Emmanuel
Martinod removed the diseased part of
the bronchus and grafted a
replacement, thus saving the lung.

The transplant, carried out in a three-
hour operation on October 28 2009,
entailed a small metal tube-shaped
frame, or stent, which supported a
section of artery taken from a
deceased donor and frozen in a tissue
bank.

The advantage of aortal tissue is that it
does not require anti-rejection drugs,
which are not recommended for cancer
patients, whose weakened immune
system is less able to combat infection.

"The patient is doing very well,"
Martinod, a professor at the Avicenne
Hospital in eastern Paris, told a press
conference.

"He needs regular monitoring, but he's
doing fine, he's walking, he goes to his
house in the country."




LUNG IMPLANT: A STEP TOWARD  
ARTIFICIAL LUNG
There is no technology available to
support failing lung function for
patients outside the hospital.
An implantable lung assist device
would complement lung function as a
bridge to transplant or possible
destination therapy.

Advanced lung disease is
characterised by an inability to remove
carbon dioxide from the blood and
reduced oxygen uptake efficiency. A
shortage of donors can mean long
delays and high mortality rates for
those awaiting a transplant.

A device that achieves carbon
dioxide/oxygen gas exchange could
allow patients more freedom when
awaiting a lung transplant.

Now, Joseph Vacanti and coworkers at
Massachusetts General Hospital,
Boston, have developed a device that
achieves the CO2/O2 gas exchange
that, when implanted in the body, could
allow patients more freedom when
awaiting a transplant. Their design is a
microfluidic branched vascular network
through which blood flows, separated
from a gas-filled chamber by a silicone
membrane less than 10um thick.

A major challenge faced by Vacanti's
team was achieving a blood pressure
within the device's channels similar to
that in veins and arteries. They applied
computational fluid dynamics to
optimise the vascular network's
structure to avoid clotting induced by
excessive blood pressure.


SYNTHETIC CORNEA  CURED THE
BLIND
Cornea implants grown in the lab can
restore vision to the blind, according to
early clinical trial results released
today.

The trial, which took place in Sweden,
consisted of 10 adults with blindness
from disease or damage to the cornea,
the transparent outer covering of the
eye. During a two-year follow-up
period, six of the 10 patients who
received the implant saw their vision
improve. In all cases, the body
accepted the new cornea implant,
repopulating it with living cells and
nerve fibers.
There is a worldwide shortage of
donated human corneas. Current
synthetic cornea replacements carry a
high risk of complications and are only
approved for use after multiple human-
tissue transplants have failed.

The new corneal implant is
"biosynthetic," meaning it is created by
a living organism, in this case, yeast.
To make the implant, researchers at
the San Francisco-based company
Fibrogen Inc. genetically engineered
yeast to produce collagen, the protein
that makes up much of the cornea.
The research team then molded the
collagen into a contact-lens shape and
surgically implanted it in one eye of
each of 10 volunteers, who had either
advanced keratoconus (a bulging of
the cornea) or central corneal
scarring. Once implanted, the collagen
acted as a scaffold for the eye's own
cells. Like vines on a trellis, the cells
began to grow on the collagen matrix,
essentially recreating the cornea.

Over a two-year follow-up period, the
cells completely populated the corneal
implant, the researchers report  in the
journal Science Translational
Medicine. The tissue became sensitive
to touch and was covered with a thin
film of protective tears, just like a
healthy cornea. Because their new
corneas were populated with their own
cells, the patients didn't have to take
immune-suppressing drugs to prevent
rejection like most organ recipients.

While six patients showed improved
vision, two others saw no change and
two had their vision get worse. After
surgery, the patients averaged 20/110
vision with glasses. Roughly, that
means they had to stand at a distance
of 20 feet (6 meters) to read
something that someone with normal,
20/20 vision would be able to read at
110 feet (36 meters).
There are several years of more
testing is ahead before this method
can be widely used.


DR ATALA IS GRINDING OUT
ENGINEERED  BODY  ORGANS

Anthony Atala was the first to build a
functioning organ from scratch—a
bladder made cell by cell—and put it
into a patient, a child whose own
bladder was congenitally deformed.
Since that breakthrough a decade
ago, the 50-year-old pediatric
urologist, director of Wake Forest
University's Institute for Regenerative
Medicine, has moved on to cobbling up
bones, heart valves, muscles, and
some 20 other body parts.

Now he runs one of the world's premier
engineered-organ centers.

To create an artery, say, Atala plucks
some of the immature cells that make
up arterial lining and muscle from a
sample of the patient's blood and
incubates them by the billions in liquid
nutrient. The cell-rich soup is then
painted on a tube-shaped scaffold
made from flexible collagen, like the
tissue that forms the nose. (The
collagen will gradually disintegrate
once the vessel is in place.) The cells
mature, multiply further, and form an
artery. A small machine exercises the
vessel, conditioning it to function
normally after it is implanted.


DARPA'S THOUGHT CONTROLLED
PROSTHETIC ARM  
The Defense Advanced Research
Projects Agency (DARPA) has
awarded a contract for up to $34.5
million to The Johns Hopkins University
Applied Physics Laboratory (APL) in
Laurel, Md., to manage the
development and testing of the
Modular Prosthetic Limb (MPL) system
on human subjects, using a brain-
controlled interface.

APL scientists and engineers
developed the underlying technology
under DARPA's Revolutionizing
Prosthetics 2009 program, an
ambitious four-year effort to create a
prosthetic arm that would by far eclipse
the World War II era hook-and-cable
device used by most amputees. The
program has already produced two
complex prototypes, each advancing
the art of upper-arm prosthetics.

The final design - the MPL - offers 22
degrees of motion, including
independent movement of each finger,
in a package that weighs about nine
pounds (the weight of a natural limb).
Providing nearly as much dexterity as
a natural limb, the MPL is capable of
unprecedented mechanical agility and
is designed to respond to a user's
thoughts. The design is ready for
Phase 3 trials.


ARTIFICIAL PANCREAS
A closed-loop insulin delivery system --
the so-called "artificial pancreas" –-
appears to improve glucose control in
patients with type 1 diabetes even
after a large dinner accompanied by
wine, compared with insulin pump
therapy, researchers said here.
Aaron Kowalski, MD, research director
for the artificial pancreas project at the
Juvenile Diabetes Research
Foundation, which helped support the
research, said during the press
briefing that closed-loop systems
should be available "in the near term."
Medtronic has developed a closed-
loop system that transmits sensor data
to an insulin pump, but does not
include the algorithms to instruct the
pump to deploy or withhold insulin
infusions.



ARTIFICIAL ARTERY
A new artificial artery made from a
polymer that is flexible enough to
function like a real blood vessel has
been developed by British scientists.
The artery looks like a short piece of
spaghetti, and the research team from
University College London claims that
it can help in reducing chances of a
heart attack during bypass surgery.
The new graft pulses rhythmically to
match the beat of the heart. The graft
material is strong, flexible, resistant to
blood clotting and doesn't break down,
which is a major breakthrough.


GROWING KNEE CARTILAGE:
The cutting-edge MACI, or
matrixinduced chondrocyte
implantation, begins with the surgeon
scraping a small amount of healthy
cartilage from the patient's knee.
The sample is shipped to a specialist
lab, where a cocktail of chemicals coax
the cartilage cells into growing.  In the
hospital, the surgeon removes the
damaged cartilage and plugs the hole
with the lab-grown cartilage, which is
stitched into place.  

MACI

PIXIE DUST TO GROW NEW TISSUE
A powder nick-named "Pixie Dust" is
being used to save the limbs of war
heroes who have been wounded in
Afghanistan.
Surgeons have already used the dust
to save several soldiers so badly
mutilated that they were at risk of
amputation.
Made from pig bladders it has the
ability to help the human body grow
new tissue to replace large areas of a
leg or arm destroyed by blast damage.
The Extra Cellular Matrix grew nerves,
ordinary tissue and muscle where
there had been none.
Pixie dust was developed by scientists
at the Centre of Regenerative
Medicine in Pittsburgh.


ARTIFICIAL HAND
Using what's called  myoelectric linking,
the prosthetic limb  picks up electrical
impulses from  remaining muscle fibers
on the arm, transmitting those
impulses to articulating fingers and a
thumb. Some can be expensive,
costing upwards of $35,000. More
reasonably priced is the i-Limb, an
$18,000 artificial hand with articulating
fingers and thumb, each with its own
motor.



ELAD ARTIFICIAL LIVER
ELAD artificial liver to keep patient
alive temporarily by Vital Therapies Inc.
ELAD, or Extracorporeal Liver Assist
Device resides outside the body.
Mimicking a normal liver, it cleanses
the blood of toxins and waste, and
produces albumin and clotting factors.
It's not all artificial, though, with the
secret sauce inside being
"immortalized human liver cells,"
interlaced with tiny tubes through
which the patient's blood flows.



LEG IMPLANT FOR A DOG
A 50 kilo American bulldog called Roly
received a breakthrough artificial leg
implant that, once applied to humans,
could revolutionize the treatment of
accident victims or people with serious
sports injuries or bone cancers.
His implant replaces the ball and
socket of the hip joint just like a
conventional hip replacement. But the
device – known as an endoprosthetic
femur – also replaces the top of the
thigh bone with a titanium and fabric
mesh that allows tendons and muscles
to reattach.


OTHER DEVELOPMENTS
Injectable Artificial Bone by Nottingham
School of Pharmacy.

MatriStem  Wound Powder for Finger
Amputation Repairs by Acell

SynCardia Systems Inc has designed
the CardioWest temporary total
artificial heart;

Pulmonary Valve Implants by
Medtronic to replace valve between
heart and lung;

ARTIFICIAL ARTERIES PRINTED:
The 3D bio-printer, developed by US
company Organovo, is already
capable of growing arteries and its
developers say arteries 'printed' by the
device could be used in heart bypass
surgery in five years.