Insulin is produced by the pancreas and puts a brake on metabolism, so preventing too much sugar entering the bloodstream. In people with massive burns, the hormones released in response to stress such as cortisol and glucagon make the body break down its own stores of fat, muscle and protein and release large amounts of blood sugar. This in turn suppresses the immune system, hampering the ability of white blood cells called neutrophils to remove dead tissue from a wound and fight infection.

Edgar Pierre and his colleagues at the Shrivers Burns Institute at the University of Texas Medical Branch at Galveston wondered if insulin might reverse this effect. They treated six people who had severe burns over at least 41 per cent of their bodies with an intravenous infusion of insulin. The patients had all required skin grafts and were also given intravenous glucose to ensure that the insulin did not send their blood sugar levels plummeting. Their grafts healed on average after 4.7 days, compared with the usual 6.5 days.

Another natural substance which prevents tissue breakdown, growth hormone, has similar effects. But Pierre says that insulin is much cheaper and more readily available. Growth hormone, moreover, can actually raise blood sugar to dangerous levels.

The waves are the result of fine contractions in the internal layer of the myometrium, the muscle layer of the uterus. According to Edward Lyons of the University of Manitoba Health Sciences Centre in Winnipeg, the waves in healthy fertile women move upwards towards the tubes 80 per cent of the time.

“Sperm are not salmon – they don’t swim unaided upstream,” says Lyons. “They need these waves to ride on to get to the egg.” Lyons believes that the force of the waves, as well as driving the sperm towards the Fallopian tubes, also keeps them there.

Lyons and his colleague Clifford Levi used ultrasound to measure the contractions in 68 women who were seeking medical treatment for infertility. The researchers then compared the measurements with those from the same number of fertile women. Because the waves normally occur at a rate of only about three per minute, the researchers recorded the ultrasound measurements and then played them back at high speed. They found that in infertile women, the waves were weak or infrequent or moved downwards in the wrong direction towards the cervix. Some infertile women even had a “discoordinated” action in which the waves spread out from the middle in two opposite directions.

“Abnormalities in the direction, frequency or intensity of these contractions may be an important cause of unexplained infertility,” says Lyons. He says that normally, the waves occur at their maximum frequency in the middle of the menstrual cycle, when a woman is ovulating and so at her most fertile. The contractions are also stimulated by substances called prostaglandins, a component of the seminal fluid which carries the sperm.

It is vital for sperm to be speedy because the environment of the upper vagina is so acidic that only a fraction survive it. The environment is much more friendly when they reach the interior of the uterus, which is lined by a mucous membrane layer called the endometrium.

Lyons says that women with abnormal waves have their best chance of conceiving around the time of ovulation because this is when the waves are most likely to move in the right direction. If the woman has persistently poor or absent contraction waves, techniques of assisted conception can help to deliver the sperm as near to the Fallopian tubes as possible. Lyons maintains that ultrasound studies of the myometrial waves should play an important role when looking for the reasons behind infertility. “This phenomenon deserves continuing study, especially for women who are unable to become pregnant even after taking fertilty drugs,” he says.

Surgeons can operate the probe with enough precision not to damage healthy areas of the brain around the tumour. Brain tumours are normally treated by surgery, after a section of the skull has been removed – a drastic procedure known as craniotomy.

In order to diagnose the type and severity of the tumour the surgeon has to take a biopsy through a small hole in the skull. In the new treatment a thin tube is inserted through the same bur-hole. The probe then passes an electric current through the tissue heating the tumour to 80 °C for one minute.

To ensure that the probe only touches the tumour the surgeon watches the operation on a video monitor which displays images obtained by interventional magnetic resonance imaging. This type of MRI allows the surgeon to stand next to the patient, to direct the probe to the tumour accurately and to see the results of the operation.

Yoshima Anzai, who has treated 15 patients, says, “MRI provides a very clear picture of the tumours during treatment and also has the advantage of giving us immediate feedback about the effect the treatment is having on the tumour”.

Anzai, assistant professor of radiology at the University of California in Los Angeles, believes that the treatment can cure some types of tumour, although she emphasises that it is still at an early stage. She says the technique, which she calls radio-frequency ablation, is most successful on small tumours of less than 3 centimetres in diameter because treating a larger tumour could cause swelling in the surrounding brain tissue, which could in turn cause complications.

Tumours with a small supply of blood vessels respond better to the technique than those with a rich supply because the blood vessels carry the heat away making it more difficult to destroy the tumour. In nine of those treated by Anzai there was no recurrence of the tumour one year after treatment but six had tumours that had spread from other parts of the body. Secondary tumours in the brain are often treated with radiation therapy and four of the successfully treated cases had undergone previous radiation therapy that had failed to work.

Anzai says that the treatment takes up to three hours. It can be performed with a local anaesthetic and people only needed to be kept in hospital for 24 hours. Patients who have a tumour removed by conventional surgery have to spend at least one week in hospital. The technique also had the advantage that it could be repeated without causing damage.

Anzai acknowledges that it is not suitable for all types of brain tumour. Some tumours can extend beyond the area that shows up on MRI and consequently the treatment does not destroy all the cancer cells.

“Although further study is needed, MRI-guided radio-frequency ablation has the potential to replace surgery or other traditional treatments as the therapy of choice for certain patients,” says Anzai.

The new finding contradicts several British studies which suggest that back
pain after childbirth may be related to the administration of an epidural, in
which a pain-relieving drug is injected near the spine during labour and
delivery. “These findings worried patients and physicians alike, but seemed
difficult to explain,” says Philippa Groves, who led the research at
Harvard.

The Harvard study involved 1185 women who gave birth to single babies at
Beth Israel Hospital in Boston. It confirmed that a high proportion – an
average of 46 per cent – of women who have given birth suffer back pain, but
it found that the rate was the same in women who had not had an epidural as in
those who had. Also, back pain was not affected by the type of delivery –
normal vaginal, forceps or Caesarean – or by the baby’s birth weight or the
length of time it took for mothers not having Caesareans to push the baby
out.

According to Groves, back pain which occurred between one and two months
after childbirth was more frequent in women who had suffered from it
previously, especially during an earlier pregnancy. It was also more common in
heavier and in younger women.

Late-onset back pain, occurring at 12 to 18 months, was twice as common in
women who had suffered back pain during the first few months. However, 21 per
cent of women developed it for the first time at this late stage. Others who
had back pain earlier no longer suffered it. Overall, back pain at any stage
was more common in women who became pregnant again fairly soon after giving
birth, says Groves.

The treatment could be a significant weapon in the fight against liver
cancer, which has an extremely high mortality rate. Worldwide, 1.25 million
cases are diagnosed each year, and nearly 94 per cent of patients die. Because
the conventional drugs used for treatment can seriously damage the kidneys and
heart, doctors normally have to limit the dose that they give. But liver
cancer tends to be resistant to drug treatment, so high concentrations of a
drug may be needed if the tumour cannot be removed surgically.

By mixing the gel with a cancer-killing drug and injecting it directly into
the tumour, the cancer can be destroyed from the inside. Further trials are
due to start next month.

Steven Curley, associate professor of surgery at the University of Texas
Anderson Cancer Center in Houston, has tested the gel on 15 people and is
optimistic that it will provide a more effective treatment for liver cancer,
including secondary tumours that have spread from other parts of the body. The
gel, with the brand name Intradose CDDP, consists of collagen with added
adrenaline, to make blood vessels constrict and reduce the spread of the drug
to healthy parts of the liver.

In early studies on rabbits, the anticancer drug cisplatin, a simple but
highly toxic chemical containing platinum, was added to Intradose CDDP. The
treatment completely destroyed liver tumours, according to Curley. “We could
get some shrinkage of the tumours with other types of treatment we tried
before, but we never got a complete cell kill,” he says. “The collagen gel
retains the drug in the tumour for an extended period.”

Thirty minutes after injecting the gel and cisplatin into the tumours, the
levels of cisplatin were five times higher inside the tumour than when the
drug was injected without the gel. Drug levels inside the tumour 24 hours
after injection were 30 times higher. Moreover, use of the gel led to
significantly lower levels of cisplatin in liver tissue 5 centimetres away
from the cancer, and in the kidneys.

Curley cautions that drug treatment in humans using the collagen gel is
still at an early stage. In the 15 patients in the trial it produced
significant shrinkage of the tumours and only caused minor discomfort, but
larger trials are needed to establish whether the treatment is as promising as
it looks.

About one in a hundred patients wakes up while under general anaesthetic,
according to Gavin Kenny, an anaesthetist at Glasgow Royal Infirmary who
led the development of the monitoring system. Waking up is most common in
women who have received a general anaesthetic for a Caesarean operation,
as the doctor tries to give a minimum amount of anaesthetic in order to
prevent distress to the baby.

The new technique, which has been tested in around 300 patients, measures
the brain’s response to sound. The monitoring system records the brain’s
activity in response to a series of clicking sounds played to the patient
through earphones while they are under the anaesthetic.

Before surgery, electrodes are placed on the person’s scalp when they
are still awake. They measure a high level of brain activity in response
to the clicks. As the general anaesthetic takes effect and the person slips
into unconsciousness, the brain activity falls to half of the conscious
level.

Doctors usually monitor the heart rate, blood circulation and breathing
levels of people who are under an anaesthetic, but determining whether they
are aware during surgery has always proved difficult. Kenny says that this
method of measuring awareness can be reliably used to indicate when an intravenous
anaesthetic is needed.

‘It appears that this technique, which relies on the brain to process
information, could eventually provide a reliable monitor to ensure that
no patient experiences the considerable trauma of awareness during surgery,’
he says.

Kenny has worked with colleagues at the Bioengineering Unit of the University
of Strathclyde in Glasgow to develop a technique of measuring consciousness,
which he calls the level of arousal scale. This scale registers the transition
from awareness to unconsciousness. It was first tested in 11 patients who
agreed to be deliberately awakened from a general anaesthetic while undergoing
surgery. The patients had also been given a local anaesthetic so they felt
no pain when they woke up.

Kenny is planning more widespread studies with the monitor and is building
10 systems for other British hospitals.

David Birnbach and his colleagues at Columbus University College of
Physicians and Surgeons in New York carried out studies of pregnant women
who used cocaine or crack. Crack is a derivative of coccaine which can be
smoked and which has a more immediate, short-lived and addictive effect
on the body. Birnbach and his colleagues found that the risks are even greater
for such women if they need to receive a general anaesthetic while giving
birth. ‘Our results indicate that cocaine abuse increases a pregnant woman’s
likelihood of needing a Caesarean section,’ says Birnbach. ‘These women
are at an increased risk of experiencing life-threatening events during
the administration of anaesthesia for that surgery.’

Birnbach says that doctors are encountering more such women as crack
and cocaine use increases in the US. He says that most of the women in the
study denied using cocaine when questioned, thereby hampering their doctor’s
ability to prevent complications. Several women who had high blood pressure
because of cocaine use were also mistakenly thought to have pre-eclampsia,
a in pregnant women which can lead to convulsions if not treated quickly.

For high-risk women, Birnbach and his colleagues have started using
a new test which can detect cocaine in urine. In one study of 100 women
who had not registered for antenatal care during pregnancy, the test found
that 75 per cent had cocaine in their urine. In another study, more than
a third of women who underwent Caesareans and were later found to be cocaine-positive
experienced ‘at least one life-threatening event’ while under anaesthesia.

Birnbach said that for a pregnant woman who is known to be a cocaine
user and must have a Caesarean, an epidural or spinal anaesthetic is safer.
However, he emphasises that even this type of local anaesthetic, during
which the woman remains conscious during the operation, is not free of risk,
but can lead to very low blood pressure in cocaine users. Nevertheless,
an epidural is less likely to endanger the woman’s life.

The new drug, PGG-Glucan, is a purified glucose polymer, derived from
a yeast. According to Timothy Babineau, who is leading the research on the
drug at Harvard University and the Deaconess Hospital in Boston, ‘PGG-Glucan
is simply a fancy sugar water that has been designed to enhance the activity
of white blood cells.’ The new drug differs from antibiotics, which actually
attack the bacteria causing infection.

At the annual conference of the American College of Surgeons, held in
San Francisco, Babineau pointed out that for most people infection after
an operation is rare. But he predicted that the drug would find its role
in preventing infection in people who are elderly, malnourished, diabetic
or who have compromised immunity because of other illnesses. These patients
could be given the drug in an intravenous infusion before undergoing surgery.
The patients in the Boston trial were scheduled for major chest or abdominal
surgery and all fell into these high-risk categories.

With one treatment the bead is placed in an incision in the bone where
it releases a high concentration of antibiotics. The patient doesn’t have
to stay in hospital and the bead is absorbed over several weeks. The bead
is made by combining the antibiotic with polylactic acid, the material used
to make absorbable surgical stitches.

The infection that leads to osteomyelitis can develop when the sheath
around the bone is ruptured after a fracture or following surgical replacement
of a joint. Ninety per cent of acute osteomyelitis cases are caused by the
Staphylococcus bacteria. Unless effective antibiotics are given early,
an operation may be necessary to remove any bone which has been destroyed
by the infection. High doses of intravenous antibiotics need to be given
to penetrate the bony tissue, which is very dense with relatively few blood
vessels. The treatment can last from four to six weeks, and cause allergies
or inflammation at the site of the intravenous tube. The antibiotic bead
should be able to avoid these problems.

So far the bead has only been tested on rabbits, where it reduced infection
levels by 97 per cent. The technique was developed by Jason Calhoun and
colleagues at the University of Texas Medical Centre in Galveston, and he
believes it could play a ‘major role’ in the prevention or treatment of
osteomyelitis in humans. The bead would not have to contain enough antibiotic
to cure the infection completely: ‘when you get an infection under a certain
level, the body can take care of it,’ he says.

Although the bead was designed specifically for use in bones, Calhoun
says it could be applied to other procedures requiring a surgical incision
such as stomach or chest operations.

‘The bead can be fashioned to contain different antibiotics,’ Calhoun
says. ‘It can be formed into a rod or a string or some other shape to fit
a particular defect in the bone, and it can be developed to release antibiotics
over different periods of time.’ This makes it valuable for treating both
severe infection and a low level of infection which can cause pain over
months or even years.

The stimulation device has been tested on 127 patients in the US, Canada,
the Netherlands and Germany. It must be implanted surgically and is
programmed to stimulate the vagus nerve for between 30 and 90 seconds
every 5 to 15 minutes.

The device has been used only on those whose epilepsy is not controlled with
drugs. Initially, only epileptics who experienced six or more fits per month
were asked to take part in the study, but now this figure has been reduced
to include those who suffer one fit per month.

Doctors implant the stimulation device under the skin of the upper left
chest. Electrodes are extended from the tiny device up to the neck where
they are positioned around the vagus nerve. The device can be implanted
either on an outpatient basis or with an overnight stay in hospital. The
whole process takes one to two hours.

After a two-week recovery period, doctors program the device to begin
stimulating the vagus nerve, gradually increasing the level of stimulation
to the maximum that can be tolerated. It is programmed by a lead placed on
the skin above the device then connected to a computer. The device can be
reprogrammed as often as necessary.

One research team led by Basim Uthman at the Neurology Service at the
Department of Veterans’ Affairs Medical Center in Gainsville, Florida,
followed up 32 patients who have had the stimulator implanted for 18 months.
They found that after three months, the average frequency of fits had been
reduced by 26 per cent, and after 12 months by 36 per cent. At the 18-month
stage, the team found that the frequency was further reduced by 47 per cent;
in nine people, it had been reduced by 75 per cent.

Any adverse side effects occurred mainly during stimulation itself. ‘The
patient may feel tingling around the electrodes in the left neck and have
some throat pain,’ says Uthman. ‘These symptoms usually improve with time as
the patient becomes tolerant to the stimulation.’

However, a magnet gives recipients some control over the device. When placed
over the stimulator for a couple of seconds, it activates the device. Some
users have even found that they can prevent a epileptic fit from starting if
they stimulate the vagus nerve when they feel a fit coming on.