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P Berquin

Publications and source records attributed to P Berquin.

At least 19 recordsLinked to original sources
PubMed2000

Postnatal changes in Fos-like immunoreactivity evoked by hypoxia in the rat brainstem and hypothalamus.

We have recently used Fos expression in adult rats to map neuronal populations activated in the brainstem and hypothalamus during the acute ventilatory response to moderate hypoxia (O(2) 11%). Although present at birth, this response evolves postnatally. The present investigation aimed at a better understanding of these maturational processes by delineating structures that might functionally develop after birth. The developmental pattern Fos expression evoked by hypoxia was analysed in rats aged from 0 to 26 postnatal days. The numbers of Fos positive neurons markedly increased with the age in the medullary areas related to respiratory control during the 2 first postnatal weeks. Thereafter, the response plateaued in the nucleus tractus solitarius and attenuated in the ventral medulla. In the upper brainstem (parabrachial area, central grey) and the hypothalamus (posterior and dorsomedial nuclei, ventral zone), Fos response to hypoxia was absent or weak at birth and increased until late development. The significance of the development of evoked Fos expression in these rostral sites is discussed together with their possible contribution to the maturation of O(2)-sensitive chemoreflex pathways.

Age Factors↗
PubMed2000

Brainstem and hypothalamic areas involved in respiratory chemoreflexes: a Fos study in adult rats.

The adaptation to hypoxia and hypercapnia requires the activation of several anatomical structures along the neuraxis. In this study, using Fos immunoreactivity, we sought to map neuronal populations involved in chemoreflex networks activated during the responses to moderate hypoxia (O(2) 11%), and hypercapnia (CO(2) 5%) in the brainstem and the hypothalamus of the rat. In the medulla, hypoxia elicited marked and significant staining in the nucleus of the solitary tract (NTS), and in parapyramidal neurons located near the ventral surface, whereas hypercapnia evoked significantly c-fos only near the ventral surface in paraolivar neurons. In contrast, within pontine and suprapontine structures, both hypoxia and hypercapnia evoked similarly Fos immunoreactivity in the lateral parabrachialis area, the central grey, the caudal hypothalamus (dorsomedial and posterior hypothalamic nuclei), and in a ventro-lateral hypothalamic area, extending from the rostral limit of the mammillary nuclei to the retrochiasmatic area. More rostrally, labelling was observed in the paraventricular nucleus of the hypothalamus in response to hypercapnia, and in the supraoptic nucleus in response to hypoxia. These results support the hypothesis that chemoreflexes pathways are not only restricted to medulla and pons but also involved mesencephalic and hypothalamic regions. The parabrachialis area and the central grey may be key relays between caudal and ventral hypothalamic neurons, and medullary neurons involved in the response to hypoxia and hypercapnia.

Animals↗
PubMed2000

Cerebral white matter disease in children may be caused by mitochondrial respiratory chain deficiency.

Several mitochondrial diseases are known to occasionally involve the cerebral white matter, namely Leigh syndrome, Kearns-Sayre syndrome, and MELAS syndrome, but in these cases the major finding is alteration in the basal ganglia and brainstem. Here we report on severe diffuse white matter involvement and respiratory chain enzyme deficiency or mitochondrial DNA rearrangement in 5 unrelated families. It is interesting that white matter lesions were the only abnormal neuroradiologic feature in 3 of the 5 families, and multiple small cyst-like white matter lesions were found in 2 of 5 probands. Respiratory chain deficiency should be considered in the diagnosis of severe white matter involvement in childhood.

Adolescent↗
PubMed1999

[Symptomatic and cryptogenic epilepsies in the child].

Symptomatic and cryptogenic epilepsies are related to detected or suspected cerebral lesions. Early identification of defined epileptic syndromes and etiology is helpful to adapt treatment. Generalized epilepsies are severe, often refractory and generally associated with cognitive dysfunction or regression. Partial symptomatic or cryptogenic epilepsies represent about 40% of all epilepsies in childhood and diagnosis as well as therapeutic strategy can be difficult. Semiology of partial seizures is related to epileptogenic focus and discharge propagation. Causes are numerous and are to be always extensively searched.

Anticonvulsants↗
PubMed1999

[Benign infantile convulsions. French collaborative study].

BACKGROUND: Benign infantile non febrile seizures are not well known, leading us to study their clinical and EEG characteristics. METHODS: Between 1981 and 1994, we assembled 34 patients with the following inclusion criteria: non febrile seizures between 1 month and 2 years of age, normal personal history, no abnormality on clinical, biological and radiological investigations, normal developmental outcome with at least 1 year follow-up. RESULTS: These 34 patients were recognized as 14 familial cases (identical seizures affecting parents) and 11 non familial cases. The other nine cases had different or undefined epilepsy in the family. The clinical and EEG characteristics were the same: at the mean age of 6 months, brief partial seizures (often secondarily or apparently generalized) occurring in a cluster of two to 12 episodes a day for a mean duration of 2.5 days, with ictal EEG showing focal discharge, often slow waves or focal spikes on post-ictal tracing and normal interictal EEG. CONCLUSION: The clinical and EEG characteristics are important in order to recognize this type of infantile convulsions (familial or not familial), which have a good prognosis and need no aggressive treatment.

Age of Onset↗
PubMed1999

[Use of the admission service and pediatric emergency service of a university hospital center by adolescents (12-19 years): utilization and messages].

A retrospective survey concerning all patients ages 12-19 who had registered themselves at the admitting service of the paediatric emergency unit in the university hospital centre of Amiens was carried out in 1995. 2812 adolescents were received (18% of total admissions). The male/female sex-ratio was 1 to 3. The average age was 13.2 years old. Hospitalisations were more frequent in the spring and were predominantly on Mondays (17%). More than 2/3 of the adolescents were accompanied by their parents and 20% were referred by their doctors or by the SAMU (mobile emergency medical service). Two percent arrive alone. Traumatic pathology is the main reason for admission (1960 patients). Organic pathologies represent 24% of admissions and are essentially digestive pathologies (40%). "Suffering" adolescents (defined as those requiring an intervention with a psychotherapist as a matter of priority) only represent 6% of visits to the emergency unit, of which 2/3 correspond to suicide attempts. 24% of adolescents are hospitalised at the university hospital centre of Amiens within the paediatric services or specialised services (ENT, stomatology, etc.).

Academic Medical Centers↗
PubMed1997

Possible person-to-person transmission of Escherichia coli O111--associated hemolytic uremic syndrome.

Over a 3-month period, ten children (aged 1-13 years) from a 15-km radius in southern Picardy developed typical D+ hemolytic uremic syndrome (HUS). Polymerase chain reaction, using two pairs of verocytotoxin 1-(VT1) and VT2-specific oligonucleotide primers and an internal control was used to detect VT genes directly from stools samples. VT2 gene was detected in seven of nine patients' stools and in 5 of 14 contacts' stool samples. A VT2-producing Escherichia coli (VTEC) O111 was isolated from five of nine children's stools and in 3 adults' stools of the 14 tested. A retrospective case-control study was performed which showed a higher rate of absence in school A, where the first four cases were detected, compared with a control school. The odds ratio for the whole school was 2.77 (confidence interval 1.46-5.26), and 15 (confidence interval 2.54-115.6) if only the nursery classes were considered. A culture of all food samples from households was always negative for VTEC. A retrospective cohort study performed in 89% of children attending school A showed no linkage between food or drink and gastroenteritis. These findings emphasize the potential for person-to-person transmission of VT2-producing E. coli O111, since the only salient risk factor was close contact.

Adolescent↗
PubMed1997

Familial infantile convulsions and paroxysmal choreoathetosis: a new neurological syndrome linked to the pericentromeric region of human chromosome 16.

Benign infantile familial convulsions is an autosomal dominant disorder characterized by nonfebrile seizures, with the first attack occurring at age 3-12 mo. It is one of the rare forms of epilepsy that are inherited as monogenic Mendelian traits, thus providing a powerful tool for mapping genes involved in epileptic syndromes. Paroxysmal choreoathetosis is an involuntary-movement disorder characterized by attacks that occur spontaneously or are induced by a variety of stimuli. Classification is still elusive, and the epileptic nature of this movement disorder has long been discussed and remains controversial. We have studied four families from northwestern France in which benign infantile convulsions was inherited as an autosomal dominant trait together with variably expressed paroxysmal choreoathetosis. The human genome was screened with microsatellite markers regularly spaced, and strong evidence of linkage for the disease gene was obtained in the pericentromeric region of chromosome 16, with a maximum two-point LOD score, for D16S3133, of 6.76 at a recombination fraction of 0. Critical recombinants narrowed the region of interest to a 10-cM interval around the centromere. Our study provides the first genetic evidence for a common basis of convulsive and choreoathetotic disorders and will help in the understanding and classification of paroxysmal neurological syndromes.

Adult↗
PubMed1996

Fragile X mutation and FG syndrome-like phenotype.

We present data on 4 mentally retarded brothers, 2 of whom were dizygotic twins with congenital hypotonia, constipation, head size disproportionately large for length or height, and a combination of minor anomalies suggestive of FG syndrome. These brothers have a mentally retarded full sister with similar minor anomalies and an older half-brother with the Martin-Bell syndrome. The mother is mentally retarded; 4 of 7 individuals are positive for fragile X, but all have a CGG expansion ranging from 0.2-2 to 4 kb. Although the phenotype is not completely typical of the FG syndrome and the coincidence of the FMR1 mutation and segregation of the MCA/MR phenotype are highly unlikely, the FMR1 mutation may affect morphogenesis more extensively and differently than the Martin-Bell syndrome does to effect an FG syndromelike phenotype in certain families. This phenotype does not appear to be a contiguous gene syndrome, but an effect of the FMR1 mutation on an adjacent gene must be considered.

Child↗
PubMed1994

c-fos-like immunoreactivity in the cat's neuraxis following moderate hypoxia or hypercapnia.

The overall pattern of c-fos immunoreactivity was studied in the brainstem and spinal cord of cats subjected to moderate hypoxia or hypercapnia. In control cats (normoxic, normocapnic), c-fos was expressed mainly in pontine and periaqueductal grey but not in brainstem structures engaged in respiratory control nor in the spinal cord. Both hypoxia and hypercapnia induced c-fos expression in the parabrachial area (pneumotaxic center). In the retrotrapezoid nucleus, a structure involved in respiratory rhythmogenesis and chemoreception, immunoreactivity was detected in hypoxic but not in hypercapnic cats. Neurons in the nucleus raphe pallidus preferentially expressed c-fos in response to hypercapnia. Labelled neurons were concentrated in the dorsal and gelatinosus subnuclei of the solitary tract following hypoxia and hypercapnia, respectively. Our data suggest that some neurons that express c-fos in hypoxic or hypercapnic cats may be involved in coordination of cardiovascular and respiratory function.

Animals↗
PubMed1991

Trichomegaly, pigmentary degeneration of the retina and growth disturbances. A probable autosomal recessive disorder.

Two brothers are described with trichomegaly, early pigmentary degeneration of the retina, growth retardation, anterior pituitary deficiencies and peripheral neuropathy. This syndrome, initially reported in a boy by Olivers and Mac Farlane in 1965 (6), and thereafter in six sporadic cases of both sexes, is not associated with a recognizable chromosomal defect. The present report of two brothers of healthy parents with negative familial history suggests an autosomal recessive mode of inheritance of this entity.

Adult↗
PubMed1991

[Dubowitz syndrome. A diagnosis not to be missed].

Dubowitz syndrome is a rare hereditary disorder whose main features are intra-uterine and post-natal growth retardation, characteristic facies, microcephaly, mental retardation and poor feeding. Because of the eczema which was present in half of the cases after 4 years of age, it cannot be mistaken for the more frequent fetal alcohol syndrome. We report 5 cases, among whom two sibs, confirming the recessive autosomal mode of inheritance and the necessity for genetic counseling.

Abnormalities, Multiple↗
PubMed1990

[Adrenoleukodystrophy: significance for genetic counseling of the determination of very long-chain fatty acids and of molecular biology].

Juvenile adrenoleukodystrophy (ADL) is a peroxisomal, X-linked, consistently fatal condition for which no treatment is currently available. Detection of heterozygote females and antenatal diagnosis by determination of very long chain fatty acid levels are therefore mandatory. We report the case of a family with two affected first cousins but six unaffected maternal uncles. Plasma levels confirmed the usual X-linked pattern with transmission by the grandmother and ruled out the hypothesis of delayed adrenomyeloleukodystrophy in the grandfather with heterozygosis of all the daughters. Although all six sons are unaffected, two certainly heterozygote females have normal plasma very long chain fatty acid levels. Heterozygosis in these women was confirmed by family restriction fragment length polymorphism studies (TAQ1) using the St 14 probe whose reliability for the diagnosis of heterozygotes with normal plasma very long chain fatty acid levels has previously been documented.

Adrenoleukodystrophy↗
PubMed1989

[Tumor epilepsy. Apropos of a case of temporal astrocytoma].

We report the case of a 15-year-old who sustained neonatal distress and subsequently presented temporal seizures. These were ascribed only several years later to a temporal astrocytoma. Tumor-related epilepsy is infrequent in children. Tumors may be responsible for a pattern of isolated partial epilepsy of several years duration. Advances in medical imaging techniques ensure earlier diagnosis, but some CT scan images may be difficult to read. CT scan is not indicated in functional epilepsy but should be performed in partial epilepsy with no known etiology.

Adolescent↗