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E Sobel

Publications and source records attributed to E Sobel.

At least 109 records · Page 6Linked to original sources
PubMed1989

World-wide trends in multiple sclerosis mortality.

Mortality attributed to multiple sclerosis (MS) was analyzed for 35 countries around the world using World Health Organization reports from 1965 to 1984. Trends were plotted for the United States and Canada, for various regions of Europe, Israel, South America, Asia, Australia and some Pacific countries. In general, MS mortality has declined steadily in North America and most of western Europe as well as in countries with a western culture but has remained stable or increased in eastern and northern Europe. Although several Mediterranean countries reported a recent increased frequency of MS, it was not (yet?) evident in mortality data. Intensive prospective surveillance of MS frequency trends in selected regions of the world will determine the validity of the trends based on mortality.

Asia↗
PubMed1989

Stroke in the Lehigh Valley: combined risk factors for recurrent ischemic stroke.

We used the Lehigh Valley Stroke Register and a logistic regression model for the odds ratio to study the relative contribution of several factors, considered jointly, to the risk of recurrent ischemic stroke. The factors were hypertension (HT), transient ischemic attack (TIA), myocardial infarction (MI), other heart diseases (OHD), diabetes mellitus (DM), age, and sex. Among these factors MI, OHD, and TIA constituted significantly greater risk than HTN, DM, age, or sex for ischemic stroke recurrence.

Cerebrovascular Disorders↗
PubMed1989

Stroke in the Lehigh Valley: racial/ethnic differences.

We investigated black/white differences in stroke rate (standardized morbidity), severity, and subtype, and the relative frequencies of 5 primary risk factors (hypertension, diabetes, myocardial infarction, other heart diseases, and transient ischemic attack [TIA]) using the Lehigh Valley Stroke Register. Blacks had a statistically significant higher, age-adjusted rate of stroke than whites. We found no differences in stroke severity using our measures but blacks had a statistically higher proportion of lacunar stroke, while whites had a higher proportion of embolic stroke. There were no differences in proportions of thrombotic stroke or intracerebral hemorrhage. The relative frequencies of hypertension, myocardial infarction, other heart diseases, and diabetes were higher for blacks, while the relative frequency of TIA was higher for whites. These observations are consistent with other reports that blacks have a higher frequency of stroke and tend to have more small-vessel cerebrovascular pathology than whites.

Age Factors↗
PubMed1988

A prospective study of platelets and plasma proteolytic systems during the early stages of Rocky Mountain spotted fever.

We prospectively examined early changes in platelets and plasma proteolytic systems in 12 vaccinated and 6 unvaccinated volunteers in whom Rocky Mountain spotted fever developed after challenge with Rickettsia rickettsii. The platelet counts declined while the plasma concentration of beta-thromboglobulin and the ratio of beta-thromboglobulin to platelet factor 4 increased, indicating in vivo activation of platelets. Plasma levels of antithrombin III decreased and levels of fibrinopeptide A increased, indicating in vivo activation of the coagulation system. Plasma fibrinogen levels peaked at 24 hours and gradually declined; this is consistent with the behavior of fibrinogen as an acute-phase reactant. Prolongation of the prothrombin time and a decrease in plasma levels of factor VII in the absence of evidence of liver injury suggested possible activation of the extrinsic pathway of coagulation. A decline in plasma prekallikrein levels with an increase in plasma C1-inhibitor-kallikrein complexes suggested activation of kallikrein, probably through the intrinsic coagulation system. Elevations in levels of plasma fibrin-degradation products and alpha 2-antiplasmin-plasmin complexes with declines in plasminogen and alpha 2-antiplasmin levels provided evidence of activation of the fibrinolytic system. Elevated plasma levels of tissue plasminogen activator and von Willebrand factor reflected endothelial stimulation. Thus, even early in the course of Rocky Mountain spotted fever that is treated promptly, there is activation of platelets, coagulation pathways, and the fibrinolytic system. These changes may be related to endothelial perturbation, a major pathogenetic mechanism in the disorder.

Antithrombin III↗
PubMed1988

Immunological profile of chest x-ray-negative, asymptomatic asbestos workers.

Several immunologic parameters, both humoral and cellular, were studied in the serum and peripheral blood lymphocytes derived from chest x-ray-negative, asymptomatic asbestos workers. All humoral and cellular parameters were intact, except the con-A-induced T cell suppressor activity and T cell division in autologous mixed lymphocyte reaction, which were significantly elevated in the asbestos plant workers. The significance of these increased T cell activities in asbestos exposed people is not clear, and further clinical and immunological follow-up is warranted.

Antibodies, Antinuclear↗
PubMed1988

Prolonged, progressive dementia with spongiform encephalopathy: a variant of Creutzfeldt-Jakob disease?

A 46-year-old female is described with prolonged, progressive dementia and a brain biopsy consistent with Creutzfeldt-Jakob disease (CJD). She had neither myoclonic jerks nor an electroencephalogram with periodic spikes and suppression. Five of her close relatives were also demented. The nosology of CJD was discussed in the light of this case in which histopathology was characteristic of spongiform encephalopathy but the clinical features were atypical. We concluded that it would be premature to expand the traditional diagnostic criteria to include such cases as having CJD but, at the same time, it would be prudent to handle tissue, linens and surgical instruments as if they were contaminated by the resistant agent of CJD.

Biopsy↗
PubMed1988

Genetic analysis of late-onset diseases using first-degree relatives.

We consider the problem of testing that a disease with variable age at onset is an autosomal dominant or recessive genetic trait. Specific reference is made to Alzheimer's disease and recent publications proposing an autosomal dominant inheritance pattern. The pedigree structure allowed is restricted to first-degree relatives of the proband for the dominant and to sibs of the proband for the recessive hypotheses, respectively, in addition to the proband. The sampling method assumed is the one most often used in practice: single ascertainment or sampling pedigrees with probability proportional to size (pps), i.e., to the number of affected individuals within a pedigree who are in the sampling frame. The statistical methodology developed takes the sampling procedure into account and is a generalization of the Kaplan-Meier method of estimating survival functions to pps sampling.

Age Factors↗
PubMed1988

Acute stroke therapy trials: problems in patient accrual.

Temple University Hospital participated in a multicenter acute stroke trial but enrolled only one patient out of 192 screened over 2 years; other centers had similar difficulty in patient recruitment. We analyzed our screening data to determine which enrollment criteria created difficulties in recruitment and whether the problem was attributable to any single criterion or to combinations of criteria. Six individual criteria were frequent causes for exclusion; however, greater than 80% of the patients were excluded for multiple reasons. Consequently, modifying or eliminating any single criterion did not appreciably increase patient accrual. Only 17 of 210 possible pairs of criteria occurred with statistically significant frequency (p less than 0.05), and these were most likely random associations. Therefore, only by minimizing the number and stringency of enrollment criteria will patient accrual be at a level that allows the study to be completed in a timely manner with a fiscally reasonable number of centers.

Acute Disease↗
PubMed1988

Triiodothyronine and 3',5'-cyclic AMP secretion by cultured human thyroid cells in response to thyrotropin and thyroid-stimulating immunoglobulin.

We have established a relatively simple and sensitive system for measuring T3 as well as cAMP secretion using cryopreserved human thyroid cells in culture. We defined optimal culture conditions and characterized the system. T3 secretion from human thyrocytes (only 1 x 10(5) cells/well) could be stimulated in a time- and dose-dependent fashion by both TSH (doses as low as 10 mU/l) and thyroid-stimulating immunoglobulin to levels 5- to 10-fold above baseline. The response to the thyroid stimulating agents was preserved for at least 3 weeks. Experiments with inhibitors of iodothyronine synthesis (propylthiouracil and methimazole) indicated that the bulk of the TSH-stimulated T3 secretion measured apparently derives from de novo iodothyronine biosynthesis rather than preformed T3. We utilized the system to investigate some aspects in the regulation of human thyrocyte T3 and cAMP secretion. Maximum stimulation of the thyroid hormone was achieved at TSH doses capable of evoking a further rise in levels of cAMP. A rise in cAMP accumulation was observed as early as 15 min following exposure to TSH, whereas it took 1-4 days to detect a significant increase in T3 secretion. Within 6 h of incubation, the bulk of TSH-stimulated intracellular cAMP was found released into the medium. 1-methyl-3-isobutylxanthine (MIX) caused a dose-related decrease (beyond 0.1 mmol/l MIX) in TSH-stimulated T3 secretion which contrasted with a concomitant expected increase in cAMP accumulation. Hence, as also observed in adrenal and testicular tissue, xanthines at high concentration seem to exhibit a dual action: potentiation of cAMP accumulation by inhibiting phosphodiesterase activity and a concomitant reduction of hormone formation.

1-Methyl-3-isobutylxanthine↗
PubMed1988

Discordant effect of interferon on natural killer activity and tumor cell sensitivity to lysis in hairy cell leukemia.

We studied the action of alpha-interferon (IFN) and interleukin-2 (IL-2) on natural killer (NK)-rich fractions and autologous tumor cells from two patients with hairy cell leukemia (HCL). The addition of IFN or IL-2 to the NK-rich fractions resulted in a significant increase in NK activity against the autologous tumor cells. This stimulatory effect was blocked if the target hairy cells (HCs) were preincubated with either IFN or IL-2. Pretreatment of the HCs with anti-Tac antibody entirely prevented the blocking effect of IL-2 and partially the blocking effect of IFN. One patient was treated with recombinant alpha c-IFN. After 2 months there was a dramatic reduction in the number of HCs in the peripheral blood coincident with the loss of the protection effect of IFN against NK lysis of the patient's HCs. NK activity against autologous tumor cells correlated poorly with that against the K562 cell line. We conclude that there is a discordant effect of IFN and IL-2 on NK activity and HC sensitivity to lysis. The Tac receptor appears to play a role in this sensitivity. Caution should be exercised in extrapolating the effects of NK activity against K562 cells to those on HC targets.

Antineoplastic Agents↗
PubMed1987

Does delay in acquiring childhood infection increase risk of multiple sclerosis?

Multiple sclerosis (MS) appears to be more common in technically advanced countries than in underdeveloped regions and migration from one area to another at a young age affects the risk of acquiring MS. One way of explaining both the peculiar frequency distribution and the effect of migration while young is to postulate that an infection early in life decreases the chance of central demyelination. However, no specific infection has been implicated consistently. Alternatively, an aberrant host response to infection in childhood might induce central demyelination. Thus, the aberrant host response could be age-dependent. In seeking associations between age of infection and risk of MS, we observed a direct relationship: where childhood diseases were acquired early in life, the frequency of MS in that population was low; where childhood diseases tended to occur nearer adolescence, MS frequency in that population was high. Since immune responsiveness to antigenic challenges matures through early adolescence, we reason that early infection might be protective and delay in acquiring childhood infections might increase the risk of developing MS. Indeed, in experimental models, the chance of inducing chronic relapsing central demyelination is increased by using adolescent rather than newborn or mature animals. In this paper, epidemiologic evidence showing the strong association between age of infection and risk of MS is presented.

Adolescent↗
PubMed1987

Stroke in the Lehigh Valley: risk factors for recurrent stroke.

Age-specific risk of recurrent stroke for various risk factors, calculated independently, was estimated using the first year of data from the Lehigh Valley Stroke Register. The register is based on a population of more than one-half million. Among the risk factors examined, the highest overall risk of recurrent stroke, 41.4, occurred with a history of at least one transient ischemic attack (TIA). After myocardial infarction (MI), the relative risk of a recurrent stroke was 8.0, while with all other heart diseases combined it was 8.4. With diabetes, the relative risk of a recurrent stroke was 5.6; with hypertension, it was 4.5. The relative risk increased with age after TIA and MI, but not for other heart disease, diabetes, and hypertension, except in the 85+-year-old age group.

Aged↗
PubMed1987

Does delay in acquiring childhood infection increase risk of multiple sclerosis?

Multiple sclerosis (MS) appears to be more common in technically advanced countries than in underdeveloped regions, and migration from one area to another at a young age affects the risk of acquiring MS. One way of explaining both the peculiar frequency distribution and the effect of migration while young is to postulate that an infection early in life decreases the chance of central demyelination. However, no specific infection has been implicated consistently. Alternatively, an aberrant host response to infection in childhood might induce central demyelination. Thus, the aberrant host response could be age-dependent. In seeking associations between age of infection and risk of MS, we observed a direct relationship: where childhood diseases were acquired early in life, the frequency of MS in that population was low; where childhood diseases tended to occur nearer adolescence, MS frequency in that population was high. Since immune responsiveness to antigenic challenges matures through early adolescence, we reason that early infection might be protective and that delay in acquiring childhood infections might increase the risk of developing MS. Indeed, in experimental models, the chance of inducing chronic relapsing central demyelination is increased by using adolescent rather than newborn or mature animals. In this paper, epidemiologic evidence showing the strong association between age of infection and risk of MS is presented.

Age Factors↗
PubMed1986

A multiple sequence alignment program.

A program is described for simultaneously aligning two or more molecular sequences which is based on first finding common segments above a specified length and then piecing these together to maximize an alignment scoring function. Optimal as well as near-optimal alignments are found, and there is also provided a means for randomizing the given sequences for testing the statistical significance of an alignment. Alignments may be made in the original alphabets of the sequences or in user-specified alternate ones to take advantage of chemical similarities (such as hydrophobic-hydrophilic).

Amino Acid Sequence↗
PubMed1986

Standardized incidence ratios of stroke: a worldwide review.

Comparison of stroke incidence in various parts of the world is difficult because differences in diagnostic criteria, medical facilities and age-sex distributions are often not taken into account. We calculated age-sex standardized incidence ratios (SIR) of stroke in 37 regions based on recent reports. The USA (1976) was taken as the standard population. In western countries SIRs varied from 0.8 to 2.1. In China and Japan, SIRs varied from 0.7 to 3.6. While the lowest and highest SIRs differed by a factor of 5, only 6 of the 37 studies yielded a SIR of more than 2.0 or below 0.75. Of these, 4 were from China and Japan. The highest ratios were based on a very intensive door-to-door survey and probably should not be compared to less intensive studies. We conclude that world-wide variation in age-sex adjusted stroke rates is relatively small.

Adult↗
PubMed1986

Transmissible virus dementia: evaluation of a zoonotic hypothesis.

Creutzfeldt-Jakob disease (CJD) and kuru are subacute transmissible dementing encephalopathies characterized by spongiform changes in the brain. Scrapie is a similar slow viral encephalopathy which affects sheep, goats and certain other animals. Anecdotal reports suggest that Creutzfeldt-Jakob disease could be a zoonosis. To evaluate the possibility that CJD is acquired from animals, a case-control study was conducted on 26 well-documented CJD cases and 40 controls. Data were collected on exposure to animals through occupations, hobbies, sports and pets. An excess exposure to certain animals was noted among the patients compared to controls in relation to occupation (deer, monkey, squirrel; odds ratio (OR) = 8.9; p less than 0.10) and hobbies (deer, OR = 9.0; rabbit, OR = 6.0; p less than 0.05). Similarly, exposure to animal organs was significantly greater in the CJD group (OR = 20.9; p less than 0.005). Statistically significant increased exposure to sheep or goats was not found among the patients. However, since spongiform encephalopathy has a wider host range than sheep and goats, the increased exposure to certain other animals suggests that a zoonotic source for CJD should be further explored.

Adult↗