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N Herrmann

Publications and source records attributed to N Herrmann.

At least 19 recordsLinked to original sources
PubMed2004

Nuclear stopping from 0.09A to 1.93A GeV and its correlation to flow.

We present a complete systematics (excitation functions and system-size dependences) of global stopping and side flow for heavy ion reactions in the energy range between 0.09A and 1.93A GeV. For the heaviest system, Au+Au, we observe a plateau of maximal stopping extending from about 0.2A to 0.8A GeV with a fast drop on both sides. The degree of stopping, which is shown to remain significantly below the expectations of a full stopping scenario, is found to be highly correlated to the amount of side flow.

Journal Article↗
PubMed2004

Azimuthal dependence of collective expansion for symmetric heavy-ion collisions.

Detailed studies of the azimuthal dependence of the mean fragment and flow energies in the Au+Au and Xe+CsI systems are reported as a function of incident energy and centrality. Comparisons between data and model calculations show that the flow energy values along different azimuthal directions could be viewed as snapshots of the fireball expansion with different exposure times. For the same number of participating nucleons more transversally elongated participant shapes from the heavier system produce less collective transverse energy. Good agreement with Boltzmann-Uehling-Uhlenbeck calculations is obtained for a soft nuclear equation of state.

Journal Article↗
PubMed2004

[Pregnancy-associated femoral nerve affection].

BACKGROUND: Common neuropathies during pregnancy are carpal tunnel syndrome or peripheral facial paralysis. However, there is little information about femoral nerve affection during pregnancy. CASE REPORT: We report on a female at 30 weeks of gestation, complaining of pain in hips and thighs and gait difficulty. Pregnancy was normally developed. Neurological examination showed a bilateral weakness in both quadriceps and iliopsoas muscles combined with soreness in hips and thighs, without deficits of sensibility. Laboratory findings and results of a lumbar punction were normal. Pelvic ultrasound and an MRI scan of the spine and pelvis showed no mass or disc prolaps. Neuromyographic evaluation bilaterally revealed acute signs of denervation of the muscles innervated by femoral nerve. Caesarean section was performed at 32 gestational weeks, as pain was unbearable and refractory to treatment with even opiates. Post partum, pain relieved immediately, and after weeks of physiotherapy, complete remission was achieved. CONCLUSION: This unusual manifestation of a neuropathy in pregnancy could be due to pressure on the femoral nerve. The patients' anxiety can be eliminated, as the described cases in literature show an excellent prognosis. However, the severity of symptoms can lead us to necessity of premature delivery.

Female↗
PubMed2001

Recommendations for the management of behavioral and psychological symptoms of dementia.

BACKGROUND: The behavioral and psychological symptoms of dementia (BPSD) are common, serious problems that impair the quality of life for both patient and caregiver. In order to provide recommendations based upon the best available evidence, a qualitative literature review was performed. METHODS: A search of the English language medical literature published between 1966 and 2000 was performed. The quality of the studies was assessed by considering the subjects, trial design, analysis and results. Final recommendations were based upon the quality of available evidence. RESULTS: The management of BPSD begins with a thorough assessment to search for underlying causes of behaviour change. Concomitant medical illness should be treated and sensory impairment ameliorated. Nonpharmacological approaches should be instituted prior to medication use. These interventions include music, light, changes in level of stimulation and specific behavioral techniques. Antipsychotics are the best studied pharmacological intervention for agitation and aggression and have demonstrated modest but consistent efficacy. Antidepressants such as trazodone and selective serotonin re-uptake inhibitors, as well as anticonvulsants such as carbamazepine and valproic acid have also demonstrated efficacy. Benzodiazepines can be used for short-term treatment as p.r.n. agents when necessary. Pharmacotherapy must be monitored closely for both effectiveness and side effects, with consideration of medication withdrawal when appropriate. CONCLUSION: The management of BPSD can significantly improve the quality of life for the patient and caregiver. Their assessment and management are essential components of the treatment of dementia.

Aged↗
PubMed2001

Role of serotonin in the behavioral and psychological symptoms of dementia.

The behavioral and psychological symptoms of dementia (BPSD) can have serious debilitating effects on the patient and increase caregiver burden. Investigations into the underlying neuropathology indicate that the serotonergic system may contribute to BPSD. In addition, serotonergic pathways are known to interact extensively with the cholinergic, noradrenergic, GABAergic, and dopaminergic systems. Hence, serotonergic therapies may be used to manipulate other neurotransmitters systems to alleviate BPSD or in combination with agents specific for the other neurotransmitter receptor sites. Neurotransmitter-modulated behaviors and evidence provided by pharmacological interventions are reviewed, focusing primarily on the serotonergic system.

Aged↗
PubMed2001

Use of prescription and nonprescription hypnotics in a Canadian elderly population.

BACKGROUND: Hypnotics are commonly used by older adults, yet little is known about the patterns of their use and effectiveness in this population. METHODS: Three thousand eight hundred sixty anonymous, self-report surveys were distributed to community pharmacies (n=356) across Canada to obtain information on the patterns of use of hypnotics from elderly volunteers. RESULTS: The mean age of respondents was 72+/-7 years (range 60 to 95 years) and 66% were women. In the past year, 53% of respondents used hypnotics. Prescription products accounted for 83% of the past year's use (66% benzodiazepines, 11% zopiclone, 4% antidepressants, 2% opioids), and 17% of the products used were over-the-counter (5% herbal, 5% antihistamines, 3% analgesics). Use was regular (50% daily) and chronic (mean duration six years: range two weeks to 30 years). Hypnotics significantly (P<0.001) improved subjective sleep latency (mean 32 min compared with 93 min), number of nocturnal awakenings (mean two compared with four) and total hours of sleep (mean 7 h compared with 4 h). Effectiveness was highly rated: at the most recent use of the product, mean 7.6 (SD+/-2.2) of 10; initially, 7.9 (SD+/-2.3) with a significance of P=0.02. Most respondents (59%) reported side effects, mainly dry mouth (30%), memory problems (22%) and daytime sleepiness (22%), although 60% rated the side effects as mild. The mean number of other medications used was five (range zero to 17). Of the 54 subjects who used nonprescription sleep products, only half (52%) indicated that their physician was aware of this use. CONCLUSIONS: Prescription drugs were primarily used for sleep and were perceived to be effective even with long term use, despite mild side effects.

Aged↗
PubMed2000

Donepezil for behavioural disorders associated with Lewy bodies: a case series.

Dementia with Lewy bodies (DLB) has been associated with important behavioural disturbances, such as psychotic symptoms. Unfortunately, neuroleptic sensitivity in these patients limits effective pharmacological management of these symptoms. Seven patients, five male and two female (mean age 75.3+/-4.7 years, range 68-81), diagnosed with DLB were treated with the acetylcholinesterase inhibitor donepezil (5-10 mg once daily) to determine its effect on treating behavioural disorders. Although the intended length of treatment was a minimum of 8 weeks, only three patients completed 8 weeks of therapy, one patient completed 6 weeks, two patients completed 4 weeks and one patient was discontinued after 5 days. The primary outcome (behavioural disturbances) was measured prospectively by the Neuropsychiatric Inventory (NPI), while other outcomes included cognition (Mini-Mental State Examination (MMSE)) and Clinical Global Impression. Three of the seven subjects showed marked improvement in behaviour, with NPI scores dropping significantly over time. Donepezil therapy was discontinued prematurely in three of the cases due to insufficient response and/or adverse events. Overall, five of the seven patients were rated at least minimally improved in behavioural symptoms. Our experience with donepezil in this group of patients shows promise. Given the limited experience with this agent in treating behavioural disorders associated with DLB, further studies are warranted.

Aged↗
PubMed2000

Effectiveness of gabapentin for the treatment of behavioral disorders in dementia.

Twelve patients with moderate to severe dementia and severe behavioral disorders were treated with open-label gabapentin (200-1,200 mg/day) for 8 weeks in a prospective case-series design. Patients were nonresponders to previous trials of neuroleptics. Behaviors were measured at 2-week intervals with the Neuropsychiatric Inventory (NPI), the Cohen-Mansfield Agitation Inventory (CMAI), and the Clinical Global Impression Scale (CGI). Gabapentin was generally well tolerated in this population. Although 42% of patients experienced adverse events such as gait instability and sedation, only two patients discontinued treatment prematurely because of adverse events. Average patient scores for the CMAI and the NPI remained unchanged after gabapentin. On the CGI, two patients were much improved, three were minimally improved, six were unchanged, and one was minimally worse. Gabapentin may have a role in treating a subgroup of dementia patients with severe behavioral disorders who have not responded to neuroleptics.

Acetates↗
PubMed2000

Dose-response evaluation of the interaction between sertraline and alprazolam in vivo.

In vitro data show the inhibition of alprazolam metabolism by sertraline via CYP3A4; therefore, using a randomized, double-blind, placebo-controlled design, the authors conducted this study to assess the potential for similar in vivo inhibition in humans. Ten healthy volunteers participated in two test sessions (placebo/alprazolam 1 mg orally) before the initiation of sertraline treatment. Blood samples were obtained over a 32-hour period and pharmacodynamic measures (sedation, psychomotor performance, memory function) were obtained over an 8-hour period. After a minimum of 2 weeks of daily sertraline self-administration (50, 100, or 150 mg/day), test sessions were repeated. Alprazolam concentrations (N = 6, 4, and 6 at sertraline doses of 50, 100, and 150 mg/day, respectively) showed no significant changes based on peak concentration (Cmax), time to maximum concentration (Tmax), elimination half-life (t1/2[beta]), and area under the concentration-time curve (AUC(0-8)), with the exception of a reduced Cmax in the 50 mg/day group. Similarly, dynamic data showed no significant variations based on peak effect, Tmax, and AUC(0-infinity), with the exception of increased peak impairment in one measure of psychomotor performance. No differences were detected between placebo alone and placebo plus sertraline. These findings suggest that sertraline (50-150 mg/day) does not alter the single-dose kinetics or dynamics of alprazolam; therefore, the combination may be prescribed without an increased risk of alprazolam toxicity.

Adult↗
PubMed2000

Functional and neuroanatomic correlations in poststroke depression: the Sunnybrook Stroke Study.

BACKGROUND AND PURPOSE: The purpose of our study was to determine the functional and neuroanatomic correlates of poststroke depressive symptoms. METHODS: Patients with consecutive admissions to a regional stroke center for new-onset unilateral hemispheric stroke who met World Health Organization and National Institute of Neurological and Communicative Disorders and Stroke criteria were eligible for inclusion in a longitudinal study. Acutely, patients underwent CT scanning, and at 3 months and 1 year after stroke, depressive symptoms were assessed by using both the Montgomery-Asberg Depression Rating Scale and the Zung Self-Rating Depression Scale. The Functional Independence Measure (FIM) served as an indication of functional outcome and was obtained at 1 month, 3 months, and 1 year after stroke, along with other demographic information. The Talairach and Tournoux stereotactic atlas was used for the primary determination of CT lesion localization. Lesion proximity to the anterior frontal pole was also measured. RESULTS: Eighty-one patients participated in the longitudinal study. Stepwise linear regression analyses generated a highly significant model (F(3,76)=9.8, R(2)=28%, P<0.0005), with lower 1-month total FIM scores, living at home, and damage to the inferior frontal region predicting higher depression scores at 3 months. Similarly, lower 3-month total FIM scores correlated with higher 3-month depression scores, and lower 1-year total FIM scores correlated with higher 1-year depression scores. CONCLUSIONS: Functional measures correlated with poststroke depression across time and, together with neuroanatomic measures, predicted depressive symptoms longitudinally. Although inferior frontal lesion location, irrespective of side, appeared to play a role as a risk factor in this study, the degree of functional dependence after stroke imparted the greatest risk.

Activities of Daily Living↗
PubMed2000

Use of SSRIs in the elderly: obvious benefits but unappreciated risks.

Selective serotonin reuptake inhibitors (SSRIs) are frequently recommended as a first-line treatment for depression in elderly patients. The evidence for this recommendation appears to be weak because studies that have examined the comparative efficacy, safety, tolerability and effectiveness of SSRIs and tricyclic antidepressants (TCAs) suggest that there are few advantages for one over another. Furthermore, a number of potential adverse effects of SSRIs are unappreciated risks. These include falls, hyponatremia, weight loss, sexual dysfunction and drug interactions. These potential risks, however, appear to be equally balanced by advantages such as fewer anticholinergic effects, a benign cardiovascular profile, ease of use and safety in overdose. SSRIs and TCAs have relative risks and benefits, and clinicians must maintain expertise in prescribing for elderly patients given both the frequency and severity of depressive disorders in late life.

Aged↗
PubMed2000

Probing peripheral and central cholinergic system responses.

OBJECTIVE: The pharmacological response to drugs that act on the cholinergic system of the iris has been used to predict deficits in central cholinergic functioning due to diseases such as Alzheimer's disease, yet correlations between central and peripheral responses have not been properly studied. This study assessed the effect of normal aging on (1) the tropicamide-induced increase in pupil diameter, and (2) the reversal of this effect with pilocarpine. Scopolamine was used as a positive control to detect age-dependent changes in central cholinergic functioning in the elderly. DESIGN: Randomized double-blind controlled trial. PARTICIPANTS: Ten healthy elderly (mean age 70) and 9 young (mean age 33) volunteers. INTERVENTIONS: Pupil diameter was monitored using a computerized infrared pupillometer over 4 hours. The study involved 4 sessions. In 1 session, tropicamide (20 microL, 0.01%) was administered to one eye and placebo to the other. In another session, tropicamide (20 microL, 0.01%) was administered to both eyes, followed 23 minutes later by the application of pilocarpine (20 microL, 0.1%) to one eye and placebo to the other. All eye drops were given in a randomized order. In 2 separate sessions, a single dose of scopolamine (0.5 mg, intravenously) or placebo was administered, and the effects on word recall were measured using the Buschke Selective Reminding Test over 2 hours. OUTCOME MEASURES: Pupil size at time points after administration of tropicamide and pilocarpine; scopolamine-induced impairment in word recall. RESULTS: There was no significant difference between elderly and young volunteers in pupillary response to tropicamide at any time point (p > 0.05). The elderly group had a significantly greater pilocarpine-induced net decrease in pupil size 85, 125, 165 and 215 minutes after administration, compared with the young group (p < 0.05). Compared with the young group, the elderly group had greater scopolamine-induced impairment in word recall 60, 90 and 120 minutes after administration (p < 0.05). CONCLUSION: There is an age-related pupillary response to pilocarpine that is not found with tropicamide. Thus, pilocarpine may be useful to assess variations in central cholinergic function in elderly patients.

Adolescent↗
PubMed1999

The nature and management of mania in old age.

Mania in old age represents a syndrome involving affective vulnerability in association with neurologic lesions that affect specific areas of the brain. Most patients suffering from mania in late life have converted to bipolarity later in life after many years and often repeated episodes of depression or else have developed mania in association with specific neurologic insults, particularly cerebrovascular disease (vascular mania). The outcome is generally worse in mania than in depression with higher prevalence of cognitive dysfunction, persistent symptoms, and greater mortality. The management of elderly bipolar patients with mood stabilizers reflects the experience with a mixed age population primarily involving the use of lithium carbonate and valproate in appropriately adjusted dosages and serum levels, with valproate having an edge on better tolerability. The use of neuroleptics is often unavoidable in initial stabilization, and electroconvulsive therapy can be life-saving in severely overactive or refractory patients.

Adult↗
PubMed1999

Prevalence of antidepressant use among older people: population-based observations.

OBJECTIVE: To assess the prevalence of antidepressant use with respect to age, gender, and time during a 5-year period from 1993 to 1997. DESIGN: A retrospective, population-based study in which data regarding a cross-sectional series of annual antidepressant use were obtained from administrative claims and census databases for more than 1.4 million older persons during calendar years 1993 through 1997. PARTICIPANTS: All residents of Ontario aged 65 or older. MAIN OUTCOME MEASURES: Changes in the prevalence of antidepressant users as a function of age group, gender, and time. RESULTS: A general, positive, linear trend in the prevalence of antidepressant users with increasing age group was consistently detected regardless of gender and year assessed (P < .001 for both genders and all years). The age-adjusted relative risk of women being dispensed an antidepressant relative to men was significantly higher during each year but seemed to decrease slightly over time: 1.74 (95% CI, 1.72-1.76) in 1993 and 1.65 (95% CI, 1.63-1.67) in 1997. The multiple linear regression model revealed significant relationships between the prevalence of antidepressant users and increasing age group, female gender, and increasing year of assessment (P < .001 for each variable). The prevalence was observed to range from a low of 5.6% in 65 to 69-year-old men in 1993 to a high of 17.2% among 85 to 89-year-old women in 1997. CONCLUSIONS: Our findings reveal that the prevalence of antidepressant users is dynamic and is significantly and independently associated with age, gender, and time of assessment.

Age Factors↗
PubMed1999

The effectiveness of antidepressants in elderly depressed outpatients: a prospective case series study.

BACKGROUND: This study examined the effectiveness of antidepressants in a group of elderly depressed outpatients by assessing depression prevalence and recording adverse events over time. METHOD: A prospective practice-based observational study (1991-1994) included consecutive outpatients at least 65 years of age with a DSM-III-R diagnosis of major affective disorder and who were prescribed antidepressant medications. Depressive symptoms were examined over time (stage 1 = 0 to 2 months; stage 2 = 2 to 6 months; stage 3 = 6 months to 2 years) with the Montgomery-Asberg Depression Rating Scale (MADRS). The cutoff scores of MADRS <18 and MADRS > or =18 were used in survival statistics. Adverse events were recorded systematically. RESULTS: A total of 213 patients were seen over 2677 visits (mean +/- SD age = 75.5+/-6.1 years). MADRS scores for 85.8% of patients declined to below 18 within the first 2 months of antidepressant treatment. MADRS scores were above 18 for 37.3% of patients after 6 months and for 37.1% after 2 years. The mean time to decline in MADRS scores to below 18 in stage 1 was 36.1 days, and there was a significant difference between the antidepressant classes (log rank = 8.3, df = 3, p = .04), with tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs)/reversible inhibitors of monoamine oxidase A (RIMAs) having shorter times to response. The mean time to reach scores above cutoff during stage 2 was 144.3 days (log rank = 5.7, df = 3, p = .13) and during stage 3, 538.6 days (log rank = 9.8, df = 3, p = .02). Patients receiving TCAs and MAOIs/RIMAs had longer durations of MADRS scores below cutoff during stage 3 than those taking atypical antidepressants and selective serotonin reuptake inhibitors. All antidepressant classes reported similar adverse event profiles. CONCLUSION: This study systematically examined antidepressant effectiveness in a prospective design. TCAs and MAOIs/RIMAs were shown to be superior in effectiveness during 2 of the 3 treatment stages.

Age Factors↗