CURRENT SCIENCE REVIEWS   By Joe Bruman   December 1997   p. 1 of 2

Tronnier V et al; J Neurosurg 1997;807:700-705:
In 6 patients given bilateral pallidal stimulation implants, they
report good improvement in dyskinesia, but only slight improvement
in gait disturbance and bradykinesia. Stimulation worsened gait
disturbance by creating a freezing phenomenon. So they question
whether DBS is a good alternative to conventional pallidotomy.

Gill S, Heywood P; Lancet, 25 Oct 1997:1224:
They dislike DBS implants because the devices are bulky and costly,
need replacement in 3-5 yr and frequent adjustment, preclude further
MRI scans, and may lose effectiveness over time. They report safe
and effective conventional ablative surgery for 2 PD patients at a
new site (bilateral, microrecorder-guided): the dorsolateral area of
the subthalamic nucleus. Both were able to quit dopamine therapy.

Vals-Sole J et al; Brain 1997;120:1877-1883:
Peculiar lack of blink reflex to a certain electrical stimulus is a
diagnostic distinction of progressive supranuclear palsy (PSP) from
PD and other parkinsonian syndromes.

Juncos J, Delong M; Sci Amer Medicine 11;Chap. XV:Nov 1997:
An 18-page chapter on PD and basal ganglia movement disorders, in
the Neurology section of a huge loose-leaf collection published
and updated sporadically for medical libraries by Scientific
American. This chapter, by two noted authorities, is the most
comprehensive and timely summary yet seen of what is known about PD.

Barbato L et al; Clin Neuropharm 1997;20:394-401:
Levodopa therapy in PD seems to have both a short-term effect,
dependent on most recent dosage, and a longer-term effect dependent
on a slower-changing "baseline" concentration of dopamine. Low
baseline level may be responsible for motor fluctuations observed
in long-term therapy. They tested combinations of Sinemet and
Ropinerole, concluding that the long-term action of levodopa may be
due to a postsynaptic effect.

van Hilten J et al; Clin Neuropharm 1997;20:402-408:
To determine a threshold of dopaminergic response of bradykinesia,
they observed tap rate and movement time in PD patients given
apomorphine, concluding that 15% gain in tap rate is a suitable
diagnostic criterion of effectiveness.

Contin M et al; Clin Neuropharm 1997;20:409-418:
In a 3-yr test of response to levodopa in 11 PD patients, the
duration of effect on tap rate declined, but that of effect on
dyskinesia showed only minor change, suggesting that the various
effects of levodopa therapy are mediated in different ways.

Del Dotto P et al; Clin Neuropharm 1997;20:455-465:
An 8-week test of the non-ergot-derived dopamine agonist Cabergoline
as adjunct to levodopa, on 10 new PD patients and 12 advanced
(fluctuating) patients, showed it to be effective treatment for
either class of patient.





CURRENT SCIENCE REVIEWS   By Joe Bruman   December 1997   p. 2 of 2

Tresilian J et al; Brain 1997;120:2093-2111:
They measured reach-and-grasp performance of PD patients, who were
about 30% slower than controls. But increasing complexity by doing
separate left- and right-hand tasks at once, or requiring greater
accuracy, didn't change the ratio. Higher (effector-independent)
levels of motor programming are preserved in PD.

Parkinson Study Group; Ann Neur 1997;42:747-755:
A 24-week controlled trial in 205 fluctuating PD patients of the
COMT inhibitor Entacapone showed it to be effective in raising
"on" duration and reducing motor fluctuations due to the "wearing-
off" effect, and well tolerated.

Hutchison W et al; Ann Neur 1997;42:767-775:
Fourteen generous pallidotomy recipients endured 80 additional
minutes in the Leksell frame for the sake of research. To confirm
a result previously found in MPTP monkeys, that the main symptoms
of PD result from reduced activity of the external globus pallidus
and overactivity in its internal region, researchers monitored 15
specific neurons using the microelectrode recording technique of
the pallidotomy procedure. After observing the imbalance, injection
of the fast-acting dopamine agonist apomorphine restored the normal
balance within 25 to 35 minutes. Then at t=80 minutes the imbalance
in neural firing rate returned to its initial state, supporting
this new insight into the pathology of PD.

Martignoni E et al; Clin Neuropharm 1996;19(1):72-80:
In a group of PD patients widely disparate in age, disease stage,
and treatment status, they found that the short-term effects of
levodopa on pituitary hormone secretion and the long-term
suppression of basal levels by terguride (a partial D2 agonist
derived from lisuride, of minimal effect on PD symptoms but strong
and persistent effect on pituitary function) to be independent.
They therefore conclude that even though dopamine is involved,
regulation of pituitary function by the hypothalamus is spared in
PD.


--
J. R. Bruman   (818) 789-3694
3527 Cody Road
Sherman Oaks, CA 91403-5013