Biomedical subjects
Publications and source records attributed to D M Dawson.
We describe 4 patients with Hodgkin's disease who developed neuralgic amyotrophy in the setting of radiation therapy. In contrast to tumor progression or radiation plexopathy, the symptom onset was abrupt and occurred within days to weeks of receiving radiation treatments. There is an association between Hodgkin's disease, radiation therapy, and neuralgic amyotrophy.
Acute myelopathies (acute transverse myelopathies) can be divided into two major groups. Vascular myelopathies are caused by aortic disease, surgery, or intrinsic vascular disease of cord vessels. Inflammatory/demyelinative myelopathies include lupus erythematosus, various viral infections, and primary demyelinating disease. Criteria for diagnostic decisions and recent data from magnetic resonance imaging are reviewed.
We review the different measurements that can be derived from recordings of compound sensory action potentials, and describe how less commonly measured aspects may be of use in clinical situations. In addition to the frequently obtained maximum conduction velocity and amplitude, minimum conduction velocity may be measured if near nerve electrodes and response averaging are used. Minimum conduction velocity is a sensitive measure of both axonal and demyelinating peripheral nerve pathology. Activity-dependent conduction is another aspect of sensory conduction that may provide additional information for the clinician. Refractory period of transmission has been used to diagnose subtle demyelinating lesions, as well as some axonal disorders. Supernormal period and the conduction of trains of stimuli may also be useful, although, at present, they remain predominantly research tools.
The scenario is all too familiar. A patient has a surgical procedure. Anesthesia is uneventful and the procedure goes well. Nothing untoward is observed in the recovery room. Later that evening the patient complains of numbness, weakness, or pain, and a neurological deficit is found. A neurologist is called, examines the patient, and it is concluded that a nerve lesion has occurred, because of stretch, ischemia, compression, or laceration. A subsequent electromyogram and nerve conduction study confirm the clinical impression, but offer little in the way of explanation. Over the subsequent months, the patient makes a slow recovery but there has been a prolonged period of pain and disability. Liability issues loom. This scenario could reflect a number of different nerve lesions. This review illustrates the different modes of pathogenesis that may occur and the variable nature of the neurological deficits. We grouped these lesions according to the clinical setting in which they occur.
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A patient presented with severe sensory loss and ataxia with total arreflexia, and elevation of CSF protein with pleocytosis. At autopsy there was extensive lymphocytic infiltration of nerves and posterior roots, sparing the anterior roots. Teased fiber preparation of nerve showed a demyelinating lesion. There were no abnormalities in the CNS. The condition appears to be an acute sensory polyneuritis bearing a close relationship to acute Guillain-Barré syndrome.
One hundred sixty-four patients with chronic progressive multiple sclerosis (MS) have been treated with a regimen of high-dose IV cyclophosphamide and ACTH over the past 6 years. Their status was reviewed to determine complications associated with treatment, dosage of medication used to induce a remission, factors which may predict a response to therapy, and subsequent course following treatment. One year following initial treatment, 81% of patients were improved or stabilized. Reprogression occurred in 69% of patients at a mean time of 17.6 months. Fifty-eight patients who initially stabilized after treatment and then reprogressed were treated a second time. One year after retreatment, 70% of these patients were improved or stabilized. Alopecia, nausea and vomiting, and minor infections were the most frequent complications. There were no deaths associated with treatment, the complication rate did not change with multiple treatments, and no late complications have yet been observed. Improvement tended to occur in younger patients with shorter disease duration. Although this treatment regimen is generally well tolerated and can favorably affect the course of chronic progressive MS in a majority of patients, a single treatment does not induce a permanent remission, and some form of maintenance treatment or retreatment is required. Current treatment programs involve testing a modified induction regimen and periodic outpatient booster injections to maintain remission.
Peyronie's disease is a localized and progressive fibrosis of unknown etiology that affects the tunica albuginea of the penis. We examined cytogenetically cell cultures derived from plaque, adjacent tunica, dermis and lymphocytes in patients with Peyronie's disease, and compared the results to cell cultures established from the tunica albuginea of control patients. Chromosomal abnormalities were detected in 9 plaque-derived cell cultures from 7 of 12 Peyronie's disease patients (58 per cent). Cells cultured from adjacent tunica, dermis and lymphocytes from the same patients were karyotypically normal, as were cultures derived from control (chordee and penile scar) patients. Chromosomal aberrations consisted of 5 numerical changes and 4 structural rearrangements, and included chromosomal additions (trisomy 7 and trisomy 8), deletions (45X,-Y), reciprocal translocations and inversions or markers. In 2 instances cultures derived from plaque tissue contained 2 independent chromosomal abnormalities. The apparently random chromosomal changes associated with Peyronie's disease suggests that karyotypic instability may be a common feature of cells within the plaque. It presently is unclear whether this finding represents multiple pathways for the development of Peyronie's disease or secondary consequences of Peyronie's disease.
Twelve patients with progressive MS were treated with a murine IgM pan-T-cell monoclonal antibody reactive against T12, a determinant present on most post-thymic T-cells. Circulating T12+ cells could not be detected from days 1 to 7, although T3+T11+T12- cells appeared by day 3. Human anti-mouse antibodies were detected in 78% of patients by day 7 and correlated with a decrease in anti-T12 MAb blood levels and the reappearance of T12+ cells in the blood. Although there were high levels of anti-T12 MAb in the serum, there were only barely detectable levels in the CSF and no decrease in the proportion of T12+ cells in the CSF with treatment. Immunologic studies demonstrated a decrease of in vitro pokeweed mitogen-driven Ig synthesis on day 3 with an increase on day 10 that consisted in part of human anti-mouse antibodies. Eleven of 12 patients completed therapy. Prednisone was administered with the treatment after mild allergic reactions occurred in the first two patients. Because this was an open phase one study and patients were treated with prednisone, the effect of treatment on the progression of disease is difficult to assess, and no definitive conclusions concerning clinical effects can be made.
Three new insect growth regulators (IGRs) were tested against Culex, Aedes and Psorophora mosquitoes. In the laboratory the 3 IGRs were active in the range of 0.3 to 1.5 ppb against Cx. quinquefasciatus. In field tests, the IGRs fenoxycarb and S-31183 formulations yielded complete control of floodwater mosquitoes at the rates of 0.005 to 0.01 lb AI/acre. In field tests against Cx. tarsalis, S-31183 formulations produced complete inhibition of emergence at the rates of 0.005 to 0.025 lb AI/acre. Fenoxycarb formulation produced similar results at the rate of 0.1 lb AI/acre. It is possible that initial and residual field activity of both IGRs can be increased by employing suitable formulations.
We have examined 138 cases of a disorder previously described in people of Portuguese origin and which has received many names. By computer analysis of 46 different items of a standardized neurological examination carried out in each patient, we have been able to delineate the main components of the clinical presentation, to conclude that the marked variability in clinical expressions does not negate the homogeneity of the disorder, and to describe the natural history of this entity which should be called, for historical reasons, "Machado-Joseph Disease". This hereditary disease has an autosomal dominant pattern of inheritance, presenting as a progressive ataxia with external ophthalmoplegia, and should be classified within the group of "Ataxic multisystem degenerations". When the disease starts before the age of 20, it may present with marked spasticity, of a non progressive nature but often so severe that it can be accompanied by "Gegenhalten" countermovements and dystonic postures but little frank dystonia. There are few true extrapyramidal symptoms except akinesia. When the disease starts after the age of 50, the clinical spectrum is mostly that of an amyotrophic polyneuropathy with fasciculations accompanying the ataxia. For all the other cases the clinical picture is a continuum between these two extremes, the main determinant of the clinical phenotype being the age of onset and a secondary factor, the place of origin of the given kindred. The ataxic and amyotrophic components are clearly progressive with time in contrast to the spasticity component. Although the majority of known cases are of Portuguese origin, this is not obligatory. The next research endeavour should be a search for the chromosomal site of the gene, using molecular biology technology such as those for recombinant DNA.
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Fifty-eight patients with severe, progressive multiple sclerosis were prospectively randomized to one of three treatments: 20 received intravenous ACTH, 20 received high-dose intravenous cyclophosphamide plus ACTH, and 18 were placed on a regimen consisting of plasma exchange, low-dose oral cyclophosphamide, and ACTH. The three groups were similar in age, sex, duration and type of disease, and degree of disability. Before treatment and six months and one year after treatment, a disability-status score, ambulation index, and functional-status score were determined, and a quantitative neurologic examination was performed. In the ACTH group, the number of patients stabilized or improved was 8 of 20 at six months and 4 of 20 at one year; in the cyclophosphamide-ACTH group, 18 of 20 at six months and 16 of 20 at one year; and in the plasma exchange group, 11 of 18 at six months and 9 of 18 at one year. High-dose cyclophosphamide plus ACTH was most effective in halting progression of the disease at both 6 and 12 months (at 12 months, cyclophosphamide-ACTH vs. ACTH, P = 0.0004; cyclophosphamide-ACTH vs. plasma exchange, P = 0.087). Thus, progressive multiple sclerosis may be stabilized by short-term, intensive immunosuppression with cyclophosphamide plus ACTH.
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Explore the source record for details and available documents.