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T A Glauser

Publications and source records attributed to T A Glauser.

59 records · Page 4Linked to original sources

Congenital brain anomalies associated with the hypoplastic left heart syndrome.

This study details the type, frequency, and clinical presentation of developmental brain anomalies in 41 infants with the hypoplastic left heart syndrome encountered during a 52-month interval. Overall, 29% of the infants had either a major or minor central nervous system abnormality. Overt central nervous system malformations, including 3 cases of agenesis of the corpus callosum and 1 case of holoprosencephaly, were seen in 4 infants (10%). Micrencephaly (brain weight at autopsy more than 2 SDs below the mean for age) was found in 27% of the infants. An immature cortical mantle was seen in 21% of the study group. Seven infants (17%) had specific recognizable patterns of malformation. The absence of dysmorphic physical features did not preclude overt or subtle central nervous system malformations. Conversely, the presence of dysmorphic features did not reliably indicate an underlying brain anomaly. Infants who had hypoplastic left heart syndrome as one of multiple nonneurologic malformations were more likely to have micrencephaly than those infants with hypoplastic left heart syndrome as an isolated abnormality. Occurrence of developmental neuropathology was elevated in those infants with hypoplastic left heart syndrome who did not have a recognizable pattern of malformation but who were small for gestational age, microcephalic, or had ocular abnormalities. Infants with hypoplastic left heart syndrome deserve careful genetic, opthalmologic, and neurologic evaluations, imaging of their intracranial anatomy, and long-term neurologic follow-up.

Abnormalities, Multiple↗

Acquired neuropathologic lesions associated with the hypoplastic left heart syndrome.

This study details the type, frequency, clinical presentation, and etiologic associations of acquired brain lesions in 40 infants with the hypoplastic left heart syndrome encountered during a 52-month interval. Detailed postmortem neuropathologic examinations showed that 55% of the infants were free of acquired brain lesions. However, the other 45% had combinations of hypoxic-ischemic lesions and intracranial hemorrhage. Central nervous system perfusion and glucose-oxygen delivery appeared to be important factors in the occurrence of hypoxic-ischemic lesions or intracranial hemorrhage, whereas acidosis and hypercarbia were not. Cerebral necrosis may be a predisposing factor for a major intracranial hemorrhage. A duration of cardiopulmonary bypass with hypothermic total circulatory arrest longer than 40 minutes was associated with a higher incidence of acquired neuropathology. These results indicate that the majority of infants with hypoplastic left heart syndrome are free of acquired neuropathology and suggest practical ways to reduce the risks in the others.

Abnormalities, Multiple↗

Reversible Horner's syndrome and Lyme disease.

Neurologic manifestations of Lyme disease are common, often debilitating, and potentially treatable. We document a case of Borrelia infection of the nervous system manifesting as a reversible Horner's syndrome. The search for Lyme disease should be part of the evaluation of an isolated central or preganglionic Horner's syndrome or any unexplained pupillary abnormality.

Adult↗

Human hepatic microsomal thiol methyltransferase. Assay conditions, biochemical properties, and correlation studies.

Thiol methyltransferase (TMT) catalyzes the S-methylation of aliphatic sulfhydryl drugs and xenobiotic compounds. As a first step in the determination of whether genetic control of TMT activity in an easily accessible human cell, the red blood cell (RBC), might reflect the regulation of TMT in the human liver, we determined optimal conditions for the assay of human hepatic microsomal TMT activity. We then used those assay conditions to study the biochemical properties and regulation of TMT in the human liver for comparison with the properties of TMT in the human RBC. Substrate kinetic studies of hepatic microsomes performed with 2-mercaptoethanol (2-ME) revealed biphasic kinetics similar to those found in the human RBC, with apparent "high-" and "low"-affinity forms of TMT activity. The high-affinity form had an optimal pH of 7.2-7.6 and apparent KM values of 9.0 microM for 2-ME and 7.5 microM for S-adenosyl-L-methionine. The low-affinity form had an optimal pH of 8.8 and apparent KM values of 20 mM for 2-ME and 44 microM for S-adenosyl-L-methionine. Both forms were inhibited by compounds that also inhibited human RBC membrane TMT. The two kinetic forms of hepatic microsomal TMT activity were inactivated approximately 50% by heating for 15 min at 53 degrees C and, as was found with RBC TMT, had very similar thermal stability profiles.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzyme Activation↗