1,720,986 research outputs found
Alternative views on beta amyloid: a disease target or a cell neuromodulator at the edge between signalling and degeneration.
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Intrathecal baclofen in patients with persistent vegetative state: 2 hypotheses
No full textSporadic cases of recovery from persistent vegetative state
(PVS) after administration of intrathecal baclofen (ITB) have
been reported without giving any possible explanation for its
paradoxical effect. We summarize our recent findings on 5
patients with PVS treated with ITB and make some speculations
on the mechanisms responsible for the observed clinical
improvement. The patients developed spasticity and were
judged eligible for ITB therapy. Two weeks after pump implantation,
patients began to show a clinical improvement that,
at the end of the 6 months’ follow-up, was stable in all but 1
patient, ranging from a mere increased alertness to a full
recovery of consciousness, as revealed by changes of the Coma
Recovery Scale–Revised (CRS-R) score. Our findings suggest
that ITB might favor a variable degree of clinical improvement.
A proposal for a pharmacodynamic explanation of this effect
has not been formally put forward. We hypothesize 2 possible
mechanisms: first, a modulation confined to spinal cord segmental
activities and to neuronal centripetal outputs reaching
the cortex; and second, a modulation of sleep-wake cycles that,
although present, may be dysregulated and interfere with alertness
and awareness. Although our research is confined to a few
subjects, it provides follow-up information by means of the
CRS-R that is a validated standardized neurobehavioral instrument
expressly designed for use in patients with PVS. Our
observations indicate that further systematic investigation of
the mechanisms and the putative clinical applications of ITB
should be undertaken
Studio dei fattori di rischio genetico nella malattia di Alzheimer: il contributo del gene codificante il recettore α (ESR1) degli estrogeni.
No full textBeta amyloid neuromodulatory activities: a challenge to beta amyloid targeting in Alzheimer's disease
No full textAwakenings and awareness recovery in disorders of consciousness is there a role for drugs?
No full textDisorders of consciousness (DOC) include coma, vegetative state (VS) and
minimally conscious state (MCS). Coma is a condition of unarousability with
a complete absence of wakefulness and awareness, whereas VS is characterized
by a lack of awareness despite a preserved wakefulness. Patients in coma
are unconscious because they lack both wakefulness and awareness. Patients
in a VS are unconscious because, although they are wakeful, they lack
awareness. Patients in a MCS show minimal but definite behavioural evidence
of self and environmental awareness.
Coma results from diffuse bilateral hemispheric lesions or selective damage
to the ascending reticular system (which is functionally connected to the
cerebral cortex by intralaminar thalamic nuclei). VS is a syndrome that is
considered to be the result of a disconnection of different cortical networks
rather than a dysfunction of a single area or a global reduction in cortical
metabolism. As revealed by functional imaging studies, clinical recovery is
often associated with a functional restoration of cortico-thalamo-cortical
connections. Depending on the amount of network restored, patients may
regain full consciousness or remain in a MCS. Molecular and neural mediators
may indirectly contribute to the above restoration processes owing to
their role in the phenomenon of neural synaptic plasticity. Therefore, there is
growing interest in the possible effects of drugs that act at the level of the CNS
in promoting emergence from DOC.
Sporadic cases of dramatic recovery from DOC after the administration of
various pharmacological agents, such as baclofen, zolpidem and amantadine,
have been recently supported by intriguing scientific observations. Analysis
of the reported cases of recovery, with particular attention paid to the condition
of the patients and to the association of their improvement with the
start of drug administration, suggests that these treatments might have promoted
the clinical improvement of some patients. These drugs are from various
and diverging classes, but can be grouped into two main categories, CNS
stimulants and CNS depressants. Some of these treatments seem to directly
encourage a consciousness restoration, while others play a more determinant role in improving cognitive domains, especially in patients with residual
cognitive impairment, than in the field of consciousness.
Given the great interest recently generated in the scientific community by
the increasing number of papers addressing this issue, further investigation of
the above treatments, with particular attention paid to their mechanisms of
action, the neurotransmitters involved and their effects on cortico-thalamocortical
circuitry, is needed
Effect of beta-amyloid in vivo infusion on dopamine release in absence of lesional effects
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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