PubMed Health⌕ Search

Biomedical subjects

E Fennell

Publications and source records attributed to E Fennell.

18 recordsLinked to original sources
PubMed1999

XLMR syndrome characterized by multiple respiratory infections, hypertelorism, severe CNS deterioration and early death localizes to distal Xq28.

We report on a family with severe X-linked mental retardation (XLMR) and progressive, severe central nervous system deterioration. Three of the five affected males died of secondary complications before the age of 10 years and none have survived past the age of 10. These complications included swallowing dysfunction and gastroesophageal reflux with secondary recurrent respiratory infections. In addition, hypotonia and a mild myopathy were also present. All had a characteristic facies, including downslanting palpebral fissures, hypertelorism, and a short nose with a low nasal bridge. The two older boys showed cerebral atrophy by CT. No metabolic abnormalities were identified. Three obligate carriers had an IQ less than 80. The causal gene has been localized distal to DXS8103 in Xq28, a region spanning 5cM. No other XLMR disorder with these manifestations have been localized to this region and this appears to be a new disorder.

Abnormalities, Multiple↗
PubMed1999

Molar tooth sign in Joubert syndrome: clinical, radiologic, and pathologic significance.

Joubert syndrome is a rare autosomal-recessive condition characterized by early hyperpnea and apnea, developmental delay, and truncal ataxia. We previously described key ocular motor signs in Joubert syndrome and the molar tooth sign resulting from dysplasia of the isthmic segment of the brain stem, superior cerebellar peduncles, and vermis. In this study, we obtained clinical and developmental data in 61 cases, and radiologic data in 46 of these, to determine the prevalence of the molar tooth sign in a large sample, and to ensure that magnetic resonance images obtained for study were representative of the Joubert syndrome population at large. We studied the morphology of the isthmic segment of the pontomesencephalic junction, the segment of the brain stem derived from the primitive isthmus. Portions of the cerebellum analyzed included the superior cerebellar peduncles, the anterior and posterior lobes of the vermis, and the flocculonodular lobe. In one case, autopsy of the brain was performed. The average age at diagnosis was 33 months. All patients were hypotonic and developmentally delayed. The molar tooth sign was present in 85% of cases with 13% of these showing additional malformations. All patients without the molar tooth sign had other mimicking conditions such as neocerebellar dysgenesis, isolated vermian atrophy, cerebellar aplasia, and cystic dilation of the cisterna magna. Autopsy showed aplasia of the cerebellar vermis with dysplasia of the dentate nucleus, elongated locus coeruleus, and marked dysplasia of the caudal medulla. A better understanding of the clinical, radiologic, and pathologic features of Joubert syndrome should help uncover the genetic basis for the syndrome.

Abnormalities, Multiple↗
PubMed1999

Parental burden, coping, and family functioning in primary caregivers of children with Joubert syndrome.

Children with Joubert syndrome have physical and intellectual disabilities. The purpose of this study was to assess the impact of Joubert syndrome on parental burden, coping, and family functioning. Forty-nine primary caregivers were surveyed. Forty-three primary caregivers were mothers and six were fathers; their mean age was 34 years. The following measures were used: Beck Depression Inventory, Child Development Inventory, Caregiver Strain Index, Family Assessment Device, and Ways of Coping Checklist-Revised. The data show that caregiver burden is not related to the severity of the child's illness, but that caregivers report significant burden. Higher burden was associated with the use of palliative coping methods, and family functioning was problematic. The results of this study suggest that for parents of children with Joubert syndrome, degree of parental burden depends more on the parents' coping skills and the level of family functioning rather than on the degree of the child's impairment. These findings highlight the importance of assessing caregiver burden, as well as decreased family functioning or coping abilities, since these problems often can be managed with psychologic intervention.

Activities of Daily Living↗
PubMed1998

Neurobehavioral development in Joubert syndrome.

Research on children with Joubert syndrome has focused on brain structural abnormalities and associated clinical symptoms. The degree of developmental delay has not been objectively reported. We investigated the neurobehavioral development of children with Joubert syndrome through neurobehavioral assessment in the largest sample to date. Thirty-two parents of children with Joubert syndrome completed the Child Development Inventory and magnetic resonance imaging (MRI) data was gathered on 17 of these children. Results indicate that 94% were severely impaired according to the Child Development Inventory, with age being positively correlated with degree of neurobehavioral impairment. The average developmental age of our sample was 19 months (63% below chronological age). Severity of illness as measured by the General Development scale of the Child Development Inventory and severity of illness as measured by MRI (overall severity rating) did not yield consistent data regarding severity of the midbrain and cerebellar malformations. Similarly, markers of abnormal cerebral development such as cortical atrophy and delayed myelination were independent of severity of illness ratings on the Child Development Inventory. The degree of developmental delay in Joubert syndrome and the severity of gross central nervous system malformations appear independent.

Adolescent↗
PubMed1997

Tapping, talking and the thalamus: possible influence of the intralaminar nuclei on basal ganglia function.

A patient with a discrete lesion of the left, intralaminar thalamic, nuclei exhibited a paradoxical finding with regard to finger-tapping. Normal subjects typically reduce their tapping rate when performing simultaneous verbal activity. Tapping was impaired in our patient's contralesional hand on baseline trials; however, performing the controlled oral word association (COWA) task, while finger-tapping, normalized her deficit. Subsequent experiments showed that motoric tasks rather than cognitive aspects of the COWA task were critical in potentiating finger-tapping performance. A SPECT study performed at rest revealed focal perfusion asymmetries in motor and premotor cortices. Because the caudal intralaminar nuclei project heavily to the striatum, striatal deafferentiation may account for these asymmetries. These observations provide some insight into the influences of the caudal intralaminar thalamic nuclei on basal ganglia function and the basal ganglia's influence on motor gating.

Adult↗
PubMed1997

Anosognosia: examining the disconnection hypothesis.

OBJECTIVE: To test the hypothesis that anosognosia for hemiparesis results from intrahemispheric disconnection. METHODS: Using right carotid barbiturate injection as a model for anosognosia for hemiparesis, systematic attempts were made to modify deficit awareness by providing the left hemisphere with explicit information regarding left upper extremity function. RESULTS: Experimental interventions failed to modify deficit awareness in 19 of 32 patients. In those patients who discovered their weakness, attempted movement of the weak limb seems more important than explicit observation of the extremity by the left hemisphere. CONCLUSIONS: The results fail to support Geschwind's disconnection hypothesis for anosognosia for hemiparesis.

Adult↗
PubMed1994

Planum temporale asymmetry and language dominance.

Language is lateralized to the left hemisphere in most individuals, and leftward asymmetry of the planum temporale has been reported in postmortem and imaging studies. In this study we measured the planum temporale on magnetic resonance imaging (MR) scans of patients (11 right-handers, 1 non-right-hander) who had selective hemispheric anesthesia or Wada testing performed for language lateralization. All subjects who had language lateralized to the left hemisphere (11 right-handers) had a leftward asymmetry of the planum temporale. One subject who had language lateralized to the right hemisphere (non-right-hander) had a strong rightward asymmetry of the planum temporale. These data suggest that planum temporale asymmetries determined by MR are associated with language dominance and may predict language laterality.

Adolescent↗
PubMed1992

Contributions of the left intralaminar and medial thalamic nuclei to memory. Comparisons and report of a case.

A patient complained of memory disturbance after a small left thalamic infarction. Neuropsychological testing revealed her memory to be normal provided that she was allowed to rehearse or use semantic encoding strategies. When these strategies were prevented, her performance was impaired. Mapping of the lesion demonstrated involvement of the caudal intralaminar nuclei (centre médian and parafascicular nuclei), and portions of the medial nuclei (medioventral [reuniens], centromedial, and the most inferior aspect of the mediodorsal nucleus). The majority of mediodorsal nucleus, the mammillary bodies, the mammillothalamic tract, and the anterior thalamic nuclei, were spared. A comparison among our patient's performances and those of alcoholic Korsakoff patients, patient NA, and amnestic patients with circumscribed diencephalic lesions suggests that there are two distinct behavioral and anatomic types of memory impairment associated with diencephalic lesions. The severe amnesia associated with damage to the mammillary bodies, midline nuclei, mammillothalamic tract, and/or dorsomedial nucleus of the thalamus (eg, Korsakoff and NA) is characterized by encoding deficits that never approximate normal performance. The memory disturbance associated with damage to the intralaminar and medial nuclei of the thalamus is milder and is characterized by severe distractibility.

Adult↗