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W DeMyer

Publications and source records attributed to W DeMyer.

At least 19 recordsLinked to original sources
PubMed1998

Pointers and pitfalls in the neurologic examination.

The neurologic examination is reviewed with regard to efficiency, technical errors, and patient comfort. Misleading nomenclature causes errors in executing and interpreting many bedside tests. The examiner can insure success by accepting every patient nonjudgmentally and by maintaining a mind-set that expects to find abnormalities. Since the examiner cannot do every possible test on every patient, intelligent utilization of the history may shorten the examination yet make it more informative. To insure full patient cooperation, the examiner should make each step in the examination into a game or contest and, wherever possible, match functions, such as muscle-to-muscle strength testing, directly against the patient's.

Foot↗
PubMed1989

Single stage repair of the median cleft lip deformity in holoprosencephaly.

A single stage repair of the median cleft lip in holoprosencephaly is presented. The use of a superiorly-based pedicle from the nasal lobule/columellar remnant for columellar creation and a free skin graft from excess horizontal lip tissue for philtral reconstruction, in addition to medial rotation of the lateral lip segments, permits complete repair in one procedure. Such an approach offers the advantage of a reduction in number of procedures and anaesthetic exposure in the severely medically compromised holoprosencephalic patient.

Abnormalities, Multiple↗
PubMed1989

Pelizaeus-Merzbacher disease: tight linkage to proteolipid protein gene exon variant.

Pelizaeus-Merzbacher disease (PMD) is a human X chromosome-linked dysmyelination disorder of the central nervous system for which the genetic defect has not yet been established. The jimpy mutation jp of the mouse is an X chromosome-linked disorder of myelin formation. The mutation is at an intron/exon splice site in the mouse gene for proteolipid protein (PLP). With the jimpy mouse mutation as a precedent, we focused our attention on the human PLP gene, which is found at Xq22. The polymerase chain reaction was used to amplify the exons of the PLP gene of an affected male from a large Indiana PMD kindred. DNA sequencing showed a C----T transition at nucleotide 40 of the second exon. An affected third cousin also showed this sequence variation, while two unaffected male relatives (sons of an obligate carrier female) had the normal cytidine nucleotide. Allele-specific oligonucleotides were used to generate data for linkage studies on the above mentioned PMD kindred. Our results show tight linkage (theta = 0) of PMD to PLP with a lod (logarithm of odds) score of 4.62. In six other unrelated PMD kindreds, only the normal-sequence oligonucleotide hybridized, which indicates genetic heterogeneity. The radical nature of the predicted amino acid change (proline to leucine), suggests that the PMD-causing defect may have been delineated in one kindred.

Base Sequence↗
PubMed1987

Serotonergic involvement in the backward tumbling response of the parlor tumbler pigeon.

The parlor tumbler is a breed of domestic pigeon which displays a hereditary movement disorder resulting in backward somersaulting upon attempting to fly. A neurochemical abnormality has been suggested to underlie this behavior. The effect on tumbling of several drugs with serotonergic actions was studied. Increasing available serotonin with 5-hydroxytryptamine (50 mg/kg) plus fluoxetine (10 mg/kg) as well as using amitriptyline (10-20 mg/kg) significantly suppressed tumbling without sedation. This suggests that serotonin mechanisms may be involved in the tumbling response.

Animals↗
PubMed1987

X-linked recessive inheritance of ataxia and adult-onset dementia: clinical features and preliminary linkage analysis.

Three generations of a family exhibit a unique syndrome of X-linked ataxia, pyramidal tract signs, and adult-onset dementia. Initial signs, manifested by 2 to 3 years of age, are delayed walking and tremor. During their teens, the patients develop mild but progressive ataxia and pyramidal tract signs. Memory problems in the third decade initiate a progressive dementia, leading to death in the sixth decade. Laboratory investigations failed to disclose a biochemical basis for the syndrome. Preliminary molecular linkage studies have been conducted, and although the specific position of the responsible gene on the X chromosome has not yet been determined, the q26-qter region and much of the p arm are unlikely sites for this gene. The linkage studies are continuing.

Adolescent↗
PubMed1984

Infantile autism.

The authors define infantile autism, giving its time of manifestation, clinical development, differential diagnosis, management, and treatment. They hypothesize that the cause of autism probably will not be found in some consistent gross alteration in brain size or gross structure but that autistic children have some generalized deficit of neurologic function that is common to most or all cerebral neurons.

Autistic Disorder↗
PubMed1980

Failure of clorazepate to cause malformations or fetal wastage in the rat.

Clorazepate dipotassium (Tranxene), an anticonvulsant benzodiazepine, was tested for teratogenicity by injecting ten pregnant Long-Evans rats with 32 mg/kg of body weight intramuscularly on days 8.5, 9.5, and 10.5 of gestation. Ten control rats similarly received sterile water injections. Sixty fetuses recovered after killing five of the mothers on day 20.5 of gestation were sectioned to ascertain external and visceral malformations. Comparison with 55 control fetuses showed no statistically significant differences in external, visceral, or skeletal malformations, nor in fetal mortality, fetal and placental weight, and crown-rump length. Five clorazepate-treated rat mothers were allowed to deliver their 45 offspring for a companion study of possible behavioral effects. None of these additional 45 clorazepate-treated rats showed external malformations. Thus clorazepate caused no gross malformations in the rat under the conditions of this study.

Abnormalities, Drug-Induced↗
PubMed1980

Delayed maze-learning in rats after prenatal exposure to clorazepate.

Five pregnant Long-Evans rats were given 32 mg/kg of body weight of clorazepate dipotassium (Tranxene) intramuscularly on gestational days 8.5, 9.5, and 10.5. Five control mothers received sterile water. The control group of offspring (n = 19) and the experimental group (n = 20) were compared by means of a timetable for neurologic development and for maze learning ability. Although the experimental group was significantly slower in stomach-lifting and walking, the neurologic battery as a whole did not disclose any consistent difference. At 21 days of age, the experimental rats weighed significantly more than the control rats. On trials 10 to 14, the control group ran the maze in less than half of the time of the experimental group. The study emphasizes the need to include tests of cerebral function in addition to developmental reflexes to screen for subtle effects of teratogens, which the simpler developmental tests may miss.

Animals↗
PubMed1976

Peripheral motor and sensory neuropathy of early childhood, simulating Werdnig-Hoffmann disease.

A five-year-old girl developed neurogenic muscular atrophy during infancy. On the basis of clinical findings and a muscle biopsy study a diagnosis of infantile spinal muscular atrophy, benign type II, was entertained. As the disease progressed, involvement of sensory pathways was detected by electrophysiological studies. Examination of a sural nerve specimen suggested a chronic polyneuropathy rather than spinal muscular atrophy. These findings were confirmed at autopsy by demonstrating severe loss of myelinated axons in ventral and dorsal spinal roots, peripheral nerves and dorsal columns of the spinal cord. In addition, islands of astroglial fibers were found in ventral and dorsal spinal roots, regarded as a secondary reaction to the breakdown of myelinated axons. This unusual scarring process seems to result from nerve fiber loss during the perinatal period, since radicular glial scar tissue is not known to occur in the spinal muscular atrophies of later onset. Examination of the sensory nervous system in patients with Werdnig-Hoffmann disease appears mandatory to clarify the precise disease entity leading to infantile neurogenic muscular atrophy.

Child, Preschool↗
PubMed1975

Median facial malformations and their implications for brain malformations.

For purposes of identifying craniofacial syndromes which predict brain malformations the face can be regarded as developing from 2 sources. The median and paramedian structures derive from the embryonic segment of the face, termed the frontonasal prominence. The lateral structures of the face derive from the branchial arches. Certain patterns of median plane facial anomalies predict a severe brain malformation, while other patterns, although producing equally grotesque facial malformations, bear little association with a malformed brain. Orbital hypotelorism may occur in a variety of syndromes with microcephaly. When combined in typical patterns with other median plane facial defects, the patient almost certainly has holoprosencephaly, and has a poor prognosis for useful psychomotor development and survival. To the current knowledge of the author, every patient with orbital hypotelorism and total aplasia of the intermaxillary segment has a severely malformed brain. These patients, with only a rare exception, make no useful psychomotor progress and die in infancy. Orbital hypertelorism implies an increased risk of a neurologically abnormal patient, but neither the mental deficiency nor the prognosis for survival are as poor as in hypotelorism. When hypertelorism is combined with certain median plane facial anomalies the patient has the median cleft face syndrome and most likely has normal mentality, or only mild retardation, and has a normal prognosis for survival.

Abnormalities, Multiple↗
PubMed1971

Classification of cerebral malformations.

Brain malformations have been classified on the basis of the types of errors which occur during embryologic development. The basis of the classification is the level of formative pathogenesis at which the error occurs. Development can be artificially regarded as consisting of cytogenesis, histogenesis, and organogenesis. Although the final stage of a malformation can be classified under one of these headings, the categories are not mutually exclusive. The classification is given in the form of a dendrogram which permits any further degree of specificity or subdivision desired.

Abnormalities, Multiple↗