1977 - Centre de Référence du Syndrome d'Ondine

(1977). "Specialty conference: Reye's syndrome complicated by Ondine's
curse." WESTERN JOURNAL OF MEDICINE 126(2): 110-8. (2004). "Erratum: Anterior Spinal Artery Syndrome Complicated by the Ondine
Curse (Archives of Neuroloy (December 2003) 60 (1787-1790))." ARCHIVES OF
NEUROLOGY 61(3): 350. Abbott, S. B. G., R. L. Stornetta, et al. (2009). "Photostimulation of
retrotrapezoid nucleus Phox2b-expressing neurons in vivo produces long-
lasting activation of breathing in rats." JOURNAL OF NEUROSCIENCE 29(18):
5806-5819.
The retrotrapezoid "nucleus" (RTN), located in the rostral
ventrolateral medullary reticular formation, contains a bilateral cluster
of [similar to]1000 glutamatergic noncatecholaminergic Phox2b-expressing
propriobulbar neurons that are activated by CO2 in vivo and by
acidification in vitro. These cells are thought to function as central
respiratory chemoreceptors, but this theory still lacks a crucial piece of
evidence, namely that stimulating these particular neurons selectively in
vivo increases breathing. The present study performed in anesthetized rats
seeks to test whether this expectation is correct. We injected into the
left RTN a lentivirus that expresses the light-activated cationic channel
ChR2 (channelrhodopsin-2) (H134R mutation; fused to the fluorescent protein
mCherry) under the control of the Phox2-responsive promoter PRSx8.
Transgene expression was restricted to 423 +/- 38 Phox2b-expressing neurons
per rat consisting of noncatecholaminergic and C1 adrenergic neurons (3:2
ratio). Photostimulation delivered to the RTN region in vivo via a
fiberoptic activated the CO2-sensitive neurons vigorously, produced a long-
lasting (t1/2 = 11 s) increase in phrenic nerve activity, and caused a
small and short-lasting cardiovascular stimulation. Selective lesions of
the C1 cells eliminated the cardiovascular response but left the
respiratory stimulation intact. In rats with C1 cell lesions, the mCherry-
labeled axon terminals originating from the transfected
noncatecholaminergic neurons were present exclusively in the lower
brainstem regions that contain the respiratory pattern generator. These
results provide strong evidence that the Phox2b-expressing
noncatecholaminergic neurons of the RTN region function as central
respiratory chemoreceptors. Copyright copyright 2009 Society for
Neuroscience. Abbott, S. B. G., R. L. Stornetta, et al. (2009). "Photostimulation of
channelrhodopsin-2 expressing ventrolateral medullary neurons increases
sympathetic nerve activity and blood pressure in rats." JOURNAL OF
PHYSIOLOGY 587(23): 5613-5631.
To explore the specific contribution of the C1 neurons to blood
pressure (BP) control, we used an optogenetic approach to activate these
cells in vivo. A lentivirus that expresses channelrhodopsin-2 (ChR2) under
the control of the catecholaminergic neuron-preferring promoter PRSx8 was
introduced into the rostral ventrolateral medulla (RVLM). After 2-3 weeks,
ChR2 was largely confined to Phox2b-expressing neurons (89%). The ChR2-
expressing neurons were non-GABAergic, non-glycinergic and predominantly
catecholaminergic ([similar to]54%). Photostimulation of ChR2-transfected
RVLM neurons (473 nm, 20 Hz, 10 ms, [similar to]9 mW) increased BP (15
mmHg) and sympathetic nerve discharge (SND; 64%). Light pulses at 0.2-0.5
Hz evoked a large sympathetic nerve response (16 x baseline) followed by a
silent period (1-2 s) during which another stimulus evoked a reduced
response. Photostimulation activated most (75%) RVLM baroinhibited neurons
sampled with 1/1 action potential entrainment to the light pulses and
without accommodation during 20 Hz trains. RVLM neurons unaffected by
either CO2 or BP were light-insensitive. Botzinger respiratory neurons were
activated but their action potentials were not synchronized to the light
pulses. Juxtacellular labelling of recorded neurons revealed that, of these
three cell types, only the cardiovascular neurons expressed the transgene.
In conclusion, ChR2 expression had no discernable effect on the putative
vasomotor neurons at rest and was high enough to allow precise temporal
control of their action potentials with light pulses. Photostimulation of
RVLM neurons caused a sizable sympathoactivation and rise in blood
pressure. These results provide the most direct evidence yet that the C1
neurons have a sympathoexcitatory function. copyright 2009 The Authors.
Journal compilation copyright 2009 The Physiological Society. Aboushanab, O. A., S. A. Alotaibi, et al. (2007). "Late onset central
hypoventilation syndrome with hypothalamic dysfunction in a Kuwaiti girl."
Kuwait Medical Journal 39(4): 376-378.
Late onset central hypoventilation syndrome (LO-CHS) is now
considered a well-established disease that develops in previously normal
children after infancy and has been regarded as a distinct entity from the
congenital central hypoventilation syndrome (CCHS). Both conditions are
associated with neural crest tumours, but hypothalamic dysfunction (HD) is
a feature of LO-CHS and not CCHS. We report a case of LO-CHS with HD (LO-
CHS/HD) who presented in respiratory failure at the age of five years. Acosta, S., C. Lavarino, et al. (2009). "Comprehensive characterization of
neuroblastoma cell line subtypes reveals bilineage potential similar to
neural crest stem cells." BMC Developmental Biology 9: 12.
BACKGROUND: Neuroblastic tumors (NBT) derive from neural crest stem
cells (NCSC). Histologically, NBT are composed by neuroblasts and
Schwannian cells. In culture, neuroblastic (N-), substrate-adherent (S-)
and intermediate phenotype (I-) cell subtypes arise spontaneously. METHODS:
Here, neuroblastoma (NB) cell line subtypes were characterized according to
embryonic peripheral nervous system development markers (GAP43, Phox2b,
Sox10, c-kit, GD2, NF68, vimentin, S100beta, calcyclin and ABCG2),
morphological features, gene expression and differentiation potential. I-
type cells were investigated as a bipotential (neuronal and glial)
differentiation stage. RESULTS: Positive immunostaining of NCSC (GAP43, c-
kit, NF68, vimentin and Phox2b) and undifferentiated cell (ABCG2) markers
was observed in all NB subtypes. N- and I-type cells displayed cytoplasmic
membrane GD2 staining, while nuclear calcyclin was restricted to S-type. N-
and I-type cells showed similar phenotype and immunoreactivity pattern.
Differential gene expression was associated with each cell subtype. N- and
I-type cells displayed similar differentiation capacity towards neuronal
and glial lineage fates. S-type cells, upon induction, did not show a
neuronal-like phenotype, despite gene expression changes. CONCLUSION:
Results suggest that N- and I-type NB cell subtypes represent an immature
bilineage stage, able to progress towards neuronal and glial fates upon
induction of differentiation. S-type cells appear irreversibly committed to
a glial lineage fate. Adachi, M., D. Browne, et al. (2000). "Paired-like homeodomain proteins
Phox2a/Arix and Phox2b/NBPhox have similar genetic organization and
independently regulate dopamine beta-hydroxylase gene transcription." DNA &
Cell Biology 19(9): 539-54.
The homeodomain transcription factors Arix/Phox2a and NBPhox/Phox2b
play a role in the specification of the noradrenergic phenotype of central
and peripheral neurons. To better understand the functions of these two
factors, we have compared the genetic organization, chromosomal location,
and transcriptional regulatory properties of Arix and NBPhox. The gene
structure is very similar, with each gene containing three exons and two
introns, extending a total of approximately 5 kb. Arix and NBPhox are
unlinked in human and mouse genomes. NBPhox is located on human Chromosome
4p12 and mouse Chromosome 5, while Arix is located on human Chromosome
11q13 and mouse Chromosome 7. Both proteins bind to three sites in the
promoter proximal region of the rat dopamine beta-hydroxylase gene (DBH).
In vitro, Arix and NBPhox form DNA-independent multimers and exhibit
cooperative binding to the DB1 regulatory element, which contains two
homeodomain recognition sites. Both proteins regulate transcription from
the rat DBH promoter, and transcription is synergistically increased in the
presence of the protein kinase A catalytic subunit (PKA) plus either Arix
or NBPhox. The transcription factors exhibit similar concentration-
dependent efficacies, and when they are coexpressed, transcription is
stimulated to a value approximately equal to that seen with either factor
alone. The N-terminal segment of Arix is essential for transcriptional
regulatory activity, and this region bears 50% identity with NBPhox,
suggesting a similar mechanism of transcriptional activation of the DBH
gene. We conclude from this study that Arix and NBPhox exhibit
indistinguishable and independent transcriptional regulatory properties on
the DBH promoter. Afifi, T. O., B. J. Cox, et al. (2010). "The relation between types and
frequency of gambling activities and problem gambling among women in
Canada." Canadian Journal of Psychiatry - Revue Canadienne de Psychiatrie
55(1): 21-8.
OBJECTIVE: Canada experienced large-scale growth of the gambling
industry during the 1990s. Clinical data have indicated that substantial
proportions of people seeking help for gambling problems in Canada are
women. A