35 research outputs found
A Single Dose of Neuron-Binding Human Monoclonal Antibody Improves Spontaneous Activity in a Murine Model of Demyelination
Our laboratory demonstrated that a natural human serum antibody, sHIgM12, binds to neurons in vitro and promotes neurite outgrowth. We generated a recombinant form, rHIgM12, with identical properties. Intracerebral infection with Theiler's Murine Encephalomyelitis Virus (TMEV) of susceptible mouse strains results in chronic demyelinating disease with progressive axonal loss and neurologic dysfunction similar to progressive forms of multiple sclerosis. To study the effects of rHIgM12 on the motor function of TMEV-infected mice, we monitored spontaneous nocturnal activity over many weeks. Nocturnal behavior is a sensitive measure of rodent neurologic function because maximal activity changes are expected to occur during the normally active night time monitoring period. Mice were placed in activity boxes eight days prior to treatment to collect baseline spontaneous activity. After treatment, activity in each group was continuously recorded over 8 weeks. We chose a long 8-week monitoring period for two reasons: (1) we previously demonstrated that IgM induced remyelination is present by 5 weeks post treatment, and (2) TMEV-induced demyelinating disease in this strain progresses very slowly. Due to the long observation periods and large data sets, differences among treatment groups may be difficult to appreciate studying the original unfiltered recordings. To clearly delineate changes in the highly fluctuating original data we applied three different methods: (1) binning, (2) application of Gaussian low-pass filters (GF) and (3) polynomial fitting. Using each of the three methods we showed that compared to control IgM and saline, early treatment with rHIgM12 induced improvement in both horizontal and vertical motor function, whereas later treatment improved only horizontal activity. rHIgM12 did not alter activity of normal, uninfected mice. This study supports the hypothesis that treatment with a neuron-binding IgM not only protects neurons in vitro, but also influences functional motor improvement
Bell\u27s Palsy Preceding Parkinson\u27s Disease: A Case-Control Study
We investigated the association of Bell\u27s palsy (BP) with the subsequent risk of Parkinson\u27s disease (PD) using a case-control study design. We matched 196 incident cases of PD in Olmsted County, MN, to 196 general population controls with same age (±1 year) and sex, and we reviewed the complete medical records of cases and controls in a medical records-linkage system to detect BP. Six of the 196 patients with PD and none of the 196 controls were diagnosed with BP before PD (exact binomial probability, P = 0.02). The median age at occurrence of BP was 49.5 years (range, 15-84 years) and the median time between BP and the onset of PD was 27.5 years (range, 2-54 years). The findings were similar using a standardized incidence ratio (SIR) approach, but were not statistically significant. This initial association between BP and PD awaits replication
Increased Mortality for Neurological and Mental Diseases following Early Bilateral Oophorectomy
Pessimistic, Anxious, and Depressive Personality Traits Predict All-Cause Mortality: The Mayo Clinic Cohort Study of Personality and Aging
Objective: To study the association between several personality traits and all-cause mortality. Methods: We established a historical cohort of 7216 subjects who completed the Minnesota Multiphasic Personality Inventory (MMPI) for research at the Mayo Clinic from 1962 to 1965, and who resided within a 120-mile radius centered in Rochester, MN. A total of 7080 subjects (98.1%) were followed over four decades either actively (via a direct or proxy telephone interview) or passively (via review of medical records or by obtaining their death certificates). We examined the association of pessimistic, anxious, and depressive personality traits (as measured using MMPI scales) with all-cause mortality. Results: A total of 4634 subjects (65.5%) died during follow-up. Pessimistic, anxious, and depressive personality traits were associated with increased all-cause mortality in both men and women. In addition, we observed a linear trend of increasing risk from the first to the fourth quartile for all three scales. Results were similar in additional analyses considering the personality scores as continuous variables, in analyses combining the three personality traits into a composite neuroticism score, and in several sets of sensitivity analyses. These associations remained significant even when personality was measured early in life (ages 20-39 years). Conclusions: Our findings suggest that personality traits related to neuroticism are associated with an increased risk of all-cause mortality even when they are measured early in life. Copyright © 2009 by the American Psychosomatic Society
Multimorbidity, ageing and mortality: normative data and cohort study in an American population
Objectives To describe the percentile distribution of multimorbidity across age by sex, race and ethnicity, and to demonstrate the utility of multimorbidity percentiles to predict mortality.Design Population-based descriptive study and cohort study.Setting Olmsted County, Minnesota (USA).Participants We used the medical records-linkage system of the Rochester Epidemiology Project (REP; http://www.rochesterproject.org) to identify all residents of Olmsted County, Minnesota who reached one or more birthdays between 1 January 2005 and 31 December 2014 (10 years).Methods For each person, we obtained the count of chronic conditions (out of 20 conditions) present on each birthday by extracting all of the diagnostic codes received in the 5 years before the index birthday from the electronic indexes of the REP. To compare each person’s count to peers of same age, the counts were transformed into percentiles of the total population and displayed graphically across age by sex, race and ethnicity. In addition, quintiles 1, 2, 4 and 5 were compared with quintile 3 (reference) to predict the risk of death at 1 year, 5 years and through end of follow-up using time-to-event analyses. Follow-up was passive using the REP.Results We identified 238 010 persons who experienced a total of 1 458 094 birthdays during the study period (median of 6 birthdays per person; IQR 3–10). The percentiles of multimorbidity across age did not vary noticeably by sex, race or ethnicity. In general, there was an increased risk of mortality at 1 and 5 years for quintiles 4 and 5 of multimorbidity. The risk of mortality for quintile 5 was greater for younger age groups and for women.Conclusions The assignment of multimorbidity percentiles to persons in a population may be a simple and intuitive tool to assess relative health status, and to predict short-term mortality, especially in younger persons and in women
Long-term effects of bilateral oophorectomy on brain aging: Unanswered questions from the Mayo Clinic cohorts study of oophorectomy and aging
In the Mayo Clinic Cohort Study of Oophorectomy and Aging, women who had both ovaries removed before reaching natural menopause experienced a long-term increased risk of parkinsonism, cognitive impairment or dementia, and depressive and anxiety symptoms. Here, we discuss five possible mechanistic interpretations of the observed associations; first, the associations may be non-causal because they result from the confounding effect of genetic variants or of other risk factors; second, the associations may be mediated by an abrupt reduction in levels of circulating estrogen; third, the associations may be mediated by an abrupt reduction in levels of circulating progesterone or testosterone; fourth, the associations may be mediated by an increased release of gonadotropins by the pituitary gland; and fifth, genetic variants may modify the hormonal effects of bilateral oophorectomy through simple or more complex interactions. Results from other studies are cited as evidence for or against each possible mechanism. These putative causal mechanisms are probably intertwined, and their clarification is a research priority. © 2009 Future Medicine Ltd
Long-term risk of depressive and anxiety symptoms after early bilateral oophorectomy
© 2018 The North American Menopause Society. Objective: We studied the long-term risk of depressive and anxiety symptoms in women who underwent bilateral oophorectomy before menopause. Design: We conducted a cohort study among all women residing in Olmsted County, MN, who underwent bilateral oophorectomy before the onset of menopause for a noncancer indication from 1950 through 1987. Each member of the bilateral oophorectomy cohort was matched by age with a referent woman from the same population who had not undergone an oophorectomy. In total, we studied 666 women with bilateral oophorectomy and 673 referent women. Women were followed for a median of 24 years, and depressive and anxiety symptoms were assessed using a structured questionnaire via a direct or proxy telephone interview performed from 2001 through 2006. Results: Women who underwent bilateral oophorectomy before the onset of menopause had an increased risk of depressive symptoms diagnosed by a physician (hazard ratio=1.54, 95% CI: 1.04-2.26, adjusted for age, education, and type of interview) and of anxiety symptoms (adjusted hazard ratio=2.29, 95% CI: 1.33-3.95) compared with referent women. The findings remained consistent after excluding depressive or anxiety symptoms that first occurred within 10 years after oophorectomy. The associations were greater with younger age at oophorectomy but did not vary across indications for the oophorectomy. In addition, treatment with estrogen to age 50 years in women who underwent bilateral oophorectomy at younger ages did not modify the risk. Conclusions: Bilateral oophorectomy performed before the onset of menopause is associated with an increased long-term risk of depressive and anxiety symptoms
Increased risk of depressive and anxiety disorders in relatives of patients with Parkinson disease
Context: Relatives of patients with Parkinson disease (PD) have an increased risk of PD and other neurologic disorders; however, their risk of psychiatric disorders remains uncertain. Objective: To study the risk of depressive disorders and anxiety disorders among first-degree relatives of patients with PD compared with first-degree relatives of controls. Design, Setting, and Participants: In a population-based, historical cohort study, we included 1000 first-degree relatives of 162 patients with PD and 850 first-degree relatives of 147 controls. Both patients with PD and controls were representative of the population of Olmsted County, Minnesota. Main Outcome Measures: Documentation of psychiatric disorders was obtained for each relative separately through a combination of telephone interviews with the relatives (or their proxies) and review of their medical records from a records-linkage system (family study method). Psychiatric disorders were defined using clinical criteria from the DSM-IV or routine diagnoses. Results: We found an increased risk of several psychiatric disorders in first-degree relatives of patients with PD compared with first-degree relatives of controls (hazard ratio [HR], 1.54; 95% confidence interval [CI], 1.21-1.95; P\u3c.001). In particular, we found an increased risk of depressive disorders (HR, 1.45; 95% CI, 1.11-1.89; P=.006) and anxiety disorders (HR, 1.55; 95% CI, 1.05-2.28; P=.03). The results were consistent in analyses that adjusted for type of interview, excluded relatives who developed parkinsonism, or excluded relatives who developed both a depressive disorder and an anxiety disorder. Conclusion: These findings suggest that depressive disorders and anxiety disorders may share familial susceptibility factors with PD. ©2007 American Medical Association. All rights reserved