Search PubMed⌕ Search

Biomedical subjects

T R Swift

Publications and source records attributed to T R Swift.

At least 19 recordsLinked to original sources

Influence of age and height on nerve conduction.

Previous studies demonstrated age- and height-related slowing of nerve conduction velocity (NCV) and reduction in nerve response amplitude. Unfortunately, many studies examined discontinuous populations, preventing regression analysis. The correlation coefficients of available studies vary widely, preventing clear conclusions. We retrospectively examined 3969 clinically normal subjects ranging in age from 20 to 95 years from a total of 22,420 electrodiagnostic studies done between 1986 and 1998. The correlation of NCV with height was stronger than with age. Regression equations using both factors account for 12--27% of the variance. Responses were seen in the majority of patients aged 70 years and older, but the percentage of normals who had no response increased with advancing age. Age was strongly inversely correlated with the amplitudes of both sensory and motor responses, accounting for 7--16% of the variance. Regression equations using both height and age improved this correlation, accounting for 7--22% of the variance. Therefore, both height and age must be taken into consideration when normal values are developed.

Adult↗

Quality improvement in neurology residency programs. Report of the Quality Improvement Committee of the Association of University Professors of Neurology.

The neurology residency programs in the United States are facing a crisis of quality. The Association of University Professors of Neurology (AUPN) approved the Quality Improvement Committee to examine this situation and make recommendations, which have been accepted by the AUPN. The recommendations are (1) that the educational goals of neurology residency training be dissociated from patient-care needs in academic medical centers and (2) that minimum levels of quality be applied to residents in neurology residency programs and to these programs themselves. These minimum criteria should include minimum educational criteria for entry into the program, minimum criteria for advancement from one year to the next in the program, and minimum criteria for performance of the graduates of neurology residency programs for program accreditation. The implementation of these recommendations will require a shift of funding of the care of indigent patients from the graduate medical education budget to direct patient-care sources. These recommendations will significantly improve the quality of neurologists and neurologic care in the United States.

Academic Medical Centers↗

Ciguatera.

Ciguatera is a type of marine food poisoning produced by the consumption of ciguatoxic reef fish. The disease is of significant concern in many tropical areas where it has been known for centuries. Although mortality from ciguatera is low, morbidity is high and symptoms may be debilitating and prolonged. Ciguatera produces characteristic gastrointestinal, neurological, and to a lesser extent, cardiovascular symptoms. Though the symptoms are relatively well documented, the disease often goes unreported or misdiagnosed. The toxins responsible for ciguatera are produced by marine dinoflagellates associated with coral reefs. The toxins are ingested by and accumulate in the fishes which when consumed by man ultimately cause ciguatera. Recent advances in toxin pharmacology have identified ciguatoxin as a sodium channel agonist and have begun to address other aspects of ciguatera on the molecular level. Treatment with mannitol relieves the symptoms; the precise mechanism or mechanisms of action have not been proven. Immunoassays are being developed for detecting even negligible amounts of toxins in suspect fish flesh.

Animals↗

Improvement in sagittal sinus thrombosis by MRI.

A 33-year-old woman developed headaches, papilledema, and evanescent neurologic signs. MRI demonstrated thrombosis of the sagittal, transverse, and sigmoid sinuses. After initial heparinization and three months of oral anticoagulation therapy, papilledema was still present but the neurologic signs and symptoms had markedly improved. Repeat MRI scan revealed improvement in all dural thromboses.

Adult↗

Toward more rational nerve conduction interpretations: the effect of height.

One hundred four normal subjects ranging in age from 17 to 77 years and in height from 115 to 203 cm underwent nerve conduction studies of sural, peroneal, tibial, and median nerves. Foot temperature was measured in each patient. A strong inverse correlation was found between height and sural (r = -0.7104), peroneal (r = -0.6842), and tibial (r = -0.5044) conduction velocities. These correlations were significant at the P less than 0.001 level. Median conduction velocity was not correlated with height. Height was correlated with the distal latencies of all nerves studied (sural r = 0.6518, peroneal r = 0.4583, tibial r = 0.7217, median r = 0.5440). These correlations were significant at the P less than 0.001 level. Age was inversely correlated with both tibial (r = -0.4071) and median (r = -0.3464) nerve conduction velocities but not with sural and peroneal conductions. There were no correlations between distal latencies and age. If the variation in conduction velocity accounted for by the linear relationship with height was removed, then age would be inversely correlated to all conduction velocity measurements with the exception of the sural. Temperature is inversely correlated with the sural (r = -0.2233), peroneal (r = -0.2102), and tibial (r = -0.2710) distal latencies. In all instances, the effects of age and temperature were minor determinants when compared with the effects of height. Diagnostic conclusions made from nerve conduction data without correcting for height may be invalid in patients taller and shorter than normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Ciguatera.

Explore the source record for details and available documents.

Animals↗

Kearns-Sayre syndrome and complex II deficiency.

A 25-year-old woman with Kearns-Sayre syndrome (KSS) had complete external ophthalmoplegia, short stature, ataxia, cardiac conduction defects, and pigmentary retinopathy. Muscle biopsy revealed ragged-red fibers. Electron microscopy showed increased numbers of mitochondria with disordered structure and paracrystalline inclusions. Enzymatic analysis revealed a deficiency of complex II of the mitochondrial respiratory chain, and, more specifically, a deficiency of succinic dehydrogenase, although both subunits of this enzyme proved to be present by immunologic analysis. Therapy with vitamin cofactors did not result in short-term improvement. This appears to be the first report of complex II deficiency in a patient with KSS.

Adult↗