Search PubMed⌕ Search

Biomedical subjects

D W Williams

Publications and source records attributed to D W Williams.

At least 109 records · Page 6Linked to original sources
PubMed1974

The Roberts syndrome.

The Roberts syndrome appears to follow an autosomal recessive mode of inheritance. The cause of the abnormalities probably exerts its effect prior to the seventh week of gestation and only on a few organ systems undergoing development during this time. The peculiar morphologic features of metaphase chromosomes of the one individual who has been studied extensively are unexplained.

Abnormalities, Multiple↗
PubMedDate not supplied

Influence of centrally administered peptides on ear withdrawal from heat in the rabbit.

Certain neuropeptides previously linked to stress and implicated in CNS control of analgesia/algesia were tested using a recently developed analgesiometric model, the rabbit ear-withdrawal test. The latency to ear withdrawal increased in a dose-related manner after beta-endorphin was injected intracerebroventricularly (IVC). Intermediate doses (0.5 and 1.0 micrograms) of adrenocorticotropic hormone (ACTH) caused hyperalgesia as indicated by decreases in latency. Corticotropin-releasing factor (CRF, 0.5 and 1.0 micrograms) also caused significant hyperalgesia late in the testing period. alpha-Melanocyte stimulating hormone (alpha-MSH, 0.25-2.0 micrograms), a molecule that shares the first 13 amino acid sequence with ACTH, and somatostatin (0.25-2.0 micrograms), caused no significant change in latency. However, 1.0 microgram doses of each peptide antagonized the analgesic effect of beta-endorphin (1.0 microgram) in the following order of potency: ACTH = alpha-MSH greater than CRF greater than somatostatin. The results support the idea that CNS peptides that are released during stress can exert opposing actions on acute pain, even though they may cause little effect alone.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Cranial MR imaging in hypomelanosis of Ito.

Hypomelanosis of Ito (HI) is a rare neurocutaneous syndrome frequently associated with neurologic abnormalities. Approximately 95 cases have been reported in the literature. Intracranial findings demonstrated by magnetic resonance imaging in a patient with HI include hemimegalencephaly, abnormal white matter signal, and small discrete bilateral periventricular cysts. No gray matter heterotopias or other migrational abnormalities were identified. Periventricular cystic lesions have not been described previously in this condition.

Adolescent↗
PubMedDate not supplied

Mucopolysaccharidosis III (Sanfilippo syndrome) type B: cranial imaging in two cases.

We present the imaging findings in two patients with mucopolysaccharidosis III (Sanfilippo syndrome) type B, both with arachnoid cysts. We postulate that the deposition of glycosaminoglycans in the meninges may impair CSF flow and explain the development of arachnoid cysts also noted in patients with other forms of mucopolysaccharidoses.

Arachnoid Cysts↗
PubMedDate not supplied

Navigating the thoracic inlet.

The thoracic inlet is often seen on the "edge of the film" at computed tomography (CT); consequently, lesions affecting this structure are easily overlooked. A vascular abnormality that may be overlooked is venous thrombosis. The CT appearance of jugular vein thrombosis varies with the age of the lesion: In the acute phase, there is often loss of soft-tissue planes surrounding an enlarged, peripherally enhancing thrombus. In the chronic phase, the jugular vein appears as a tubular, nonenhancing "mass" without loss of surrounding fat planes. Intrathoracic goiters typically manifest as well-defined, markedly enhanced inhomogeneous lesions that are continuous with the cervical thyroid gland. Thyroid adenomas are typically round or oval low-attenuating lesions that enhance after contrast material administration. Thyroid carcinomas may manifest as single or multiple, irregularly shaped low-attenuating areas with or without calcification. Primary tracheal malignancies may appear as smooth or irregular, sessile or pedunculated intraluminal filling defects. Tracheomalacia manifests as destruction of the tracheal walls with soft-tissue narrowing of the tracheal lumen, whereas esophageal abnormalities manifest as thickening of the esophageal wall, dilatation of the esophageal lumen, or both. Schwannomas manifest as well-circumscribed lesions with soft-tissue attenuation that enhance after contrast material administration. Neurofibromas tend to have lower attenuation than schwannomas. Lymphangiomas typically have a cystic appearance with near water attenuation. Familiarity with the normal anatomy of the thoracic inlet as well as the CT features of related abnormalities is critical for correct diagnosis and prompt treatment.

Esophageal Diseases↗
PubMedDate not supplied

Cranial CT and MR in the Klippel-Trenaunay-Weber syndrome.

This report describes the intracranial CT and MR findings in two cases of Klippel-Trenaunay-Weber Syndrome. The findings are 1) markedly enhancing choroid plexuses, 2) severe cerebral atrophy, 3) cerebral calcifications, and 4) angiomatous leptomeningeal enhancement. The findings may resemble those seen in cases of bilateral Sturge-Weber syndrome. The two diseases should be distinguishable by the external stigmata. The authors raise the question of a spectrum of involvement in the angiodysplasias of Klippel-Trenaunay-Weber syndrome and Sturge-Weber syndrome with considerable overlap.

Brain↗
PubMedDate not supplied

Recurrent Lhermitte-Duclos disease: report of two cases and association with Cowden's disease.

Two cases of Lhermitte-Duclos disease (LDD), one associated with Cowden's disease, are reported. Both demonstrated recurrence long after initial surgical resection. There is a propensity for occurrence in the left cerebellar hemisphere. On MR there is hypointensity on T1-weighted images and moderately high signal on T2-weighted images, with parallel linear striations on the surface of the lesion felt to represent dysplastic cerebellar folia. LDD is felt to be a low-grade neoplasm and potential component of Cowden's phakomatosis.

Adult↗