Neurotransmitter replacement therapy in Alzheimer's disease.

The relative success of symptomatic attenuation of motor dysfunction in Parkinson's disease with dopaminomimetics has spurred interest in neurotransmitter replacement therapy for treating Alzheimer's disease. While cholinergic dysfunction has been linked to various clinical parameters in Alzheimer's disease, cholinergic replacement, including precursor therapy, administration of direct-acting agonists and inhibition of enzymatic degradation has had only very modest success. The inhibition of enzymatic degradation has perhaps shown the most interesting results to date.

[Comparative computerized tomography cephalometric and pharyngometric studies of patients with severe and mild sleep apnea, and in a control group].

116 males were examined. Of these, 52 belonged to a control group, whereas 40 had severe obstructive sleep apnoea (apnoea index > 20 + clinical symptoms) and 24 mild obstructive sleep apnoea (apnoea index 5-20 + clinical symptoms) (in the following, OSA signifies obstructive sleep apnoea). Cephalometry and planimetric examinations of the pharynx were performed in recumbent position with the head in neutral position and with shallow respiration.

Assessment of intellectual function in dementing disorders: validity of WAIS-R short forms for patients with Alzheimer's, Huntington's, and Parkinson's disease.

While commonly administered in the neuropsychological assessment of dementia, the Wechsler Adult Intelligence Scale-Revised (WAIS-R) is excessively long (70-90 min) and difficult for many patients. The present study examined WAIS-R data from patients with clinically distinct dementing disorders, including those with Alzheimer's, Huntington's, and Parkinson's disease (N = 148). The profiles of performance of these three patient groups across subtests were remarkably similar, suggesting that the use of a short form would not result in the loss of clinically significant information.

Heterogeneity in Alzheimer's disease: progression rate segregated by distinct neuropsychological and cerebral metabolic profiles.

In an attempt to define possible subgroups of Alzheimer's disease, 21 patients satisfying current clinical diagnostic criteria for this disorder were divided on the basis of progression rates of symptoms. Thirteen patients with relatively rapid intellectual deterioration did not differ from eight patients showing slow progression with respect to global intellectual performance, sex, or age at onset of symptoms. Neuropsychological testing revealed that although the two groups were indistinguishable in verbal or visuospatial functions associated with the parietotemporal cortex, the more rapidly deteriorating group had significantly greater impairment in executive functions attributed to the frontal lobe.

Statistical analysis of the incidence of positives in the examination of parasitological specimens.

Results of the examination of 2,000 parasitological specimens were analyzed for differences between results obtained by a technologist working in parasitology only and those obtained by general microbiologists who were also performing other laboratory work. The relative share of specimens determined to be positive by the specialist was approximately twice as high as the relative share determined by the general microbiologists.

Neuropsychological and glucose metabolic profiles in asymmetric Parkinson's disease.

Patients with predominantly unilateral parkinsonian signs may provide a unique opportunity to evaluate the cerebral representation of cognitive functions characteristically affected in idiopathic Parkinson's disease. Twenty hemiparkinsonian patients (ten left and ten right) and 10 healthy controls, matched for age and education, were studied with neuropsychological tests and positron emission tomography. Both right and left hemiparkinsonians evidenced impairments in visuospatial and verbal episodic memory function, but had no deficits in executive abilities, compared to controls.

[Recording the feeding behavior of freely moving animals using the example of freely diving Weddell seals (Leptonychotes weddellii)].

During the antarctic summer 1990, the pattern of food intake in comparison to diving-activity was investigated on adult Weddell seals. Diving depths were recorded by a time-depth recorder (TDR). The TDR is a free programmable electronic datalogger, which can store data on up to 5 channels.

[Evaluation of the postoperative "state of health" using the example of the body core temperature rhythms of sheep].

A postoperative (p.op.) estimation of "healthiness"--especially an estimation of duration of possible existing changes, caused by surgical treatment--is important not only for the ongoing of the healing up process.

Deprenyl in Parkinson's disease: mechanisms, neuroprotective effect, indications and adverse effects.

Deprenyl is a synthetic, selective inhibitor of the monoamine oxidase-B enzyme system. The mechanism of its beneficial effect in early and advanced Parkinson's disease is not settled. Increased striatal dopamine accumulation, sensitization of surviving dopamine neurons with increased dopamine production and reduced nigro-striatal toxicity may all contribute.

Diversity of mRNAs in the Axonal Compartment of Peptidergic Neurons in the Rat.

Vasopressin and oxytocin mRNAs, which are normally translated in the perikarya of magnocellular neurons, have recently been demonstrated to be also present in axons and nerve terminals which are located in the posterior pituitary. The physiological significance of this observation has not yet been resolved. In order to gain further insight into the function and plasticity of the peptidergic neuron the question was addressed whether axonal localization is a unique feature of the above-mentioned transcripts.

Axonal transport of neuropeptide encoding mRNAs within the hypothalamo-hypophyseal tract of rats.

Hypothalamic vasopressin and oxytocin transcripts have been detected in the posterior pituitary suggesting either transcription of the respective genes in pituicytes or axonal mRNA transport from the hypothalamus to the nerve terminals of the posterior pituitary. The concept of axonal mRNA transport is supported firstly, by Northern blot and in situ hybridization analysis indicating that vasopressin and oxytocin mRNAs are also present in the neural stalk; secondly, by intron analysis and transcription run on experiments demonstrating the absence of primary vasopressin and oxytocin transcripts in non-neuronal cells of the posterior pituitary; thirdly, by embryonic developmental studies showing that appearance of vasopressin transcripts in the hypothalamus and the pituitary anlage is correlated. Furthermore, during axonal transport the respective mRNAs are subject to specific modification at the poly(A) tails.

Nootropic drugs in Alzheimer's disease: symptomatic treatment with pramiracetam.

The cognitive-enhancing effects of pramiracetam in animal models of learning and memory are characterized by an inverted U-shaped dose-response curve. We evaluated antidementia efficacy of this drug in 10 patients with probable Alzheimer's disease employing a 2-phase, placebo-controlled, enrichment-type trial design. Eight patients evidenced a best dose in the dose-finding phase, but in the subsequent replication phase only two again improved to a similar degree.

Clinical trials in dementia: learning effects with repeated testing.

The possible confounding role of learning effects during multiple test administration in clinical trials in demented subjects remains uncertain. Seventeen mildly to severely affected patients with Alzheimer's disease (AD) and 16 controls were evaluated with an extensive neuropsychological battery of manually administered and computerized tests. Subjects received 3 weekly sessions using alternate test forms, to mimic a baseline, placebo, and drug condition.

Rat vasopressin and oxytocin genes are linked by a long interspersed repeated DNA element (LINE): sequence and transcriptional analysis of LINE.

Sequence analysis of the rat vasopressin and oxytocin gene family reveals that the two genes are linked by a long interspersed repeated DNA element (LINE) giving rise to seven long open reading frames encoding hypothetical proteins of 99 to 556 amino acid residues. Furthermore, although both DNA strands of LINEs serve as templates for transcription, transcripts initiated at the 3' end are more abundant than those started from the 5' end. The LINEs are transcribed preferentially in brain tissues as analyzed by Northern blot, in situ hybridization, and RNase protection experiments.

Functional characterization of estrogen and glucocorticoid responsive elements in the rat oxytocin gene.

Expression of the gene encoding the oxytocin precursor occurs in the hypothalamus and, to a lesser extent, in a number of peripheral organs, the tissue-specific regulatory mechanisms of which are largely unknown. By DNA sequence analysis several elements upstream of the transcriptional start point of the rat oxytocin gene were identified matching the consensus sequence of enhancers inducible by estrogen or glucocorticoids, respectively. Their general transactivating capacities were investigated using heterologous gene constructs and revealed that the rat oxytocin gene harbours two functional estrogen responsive elements near the transcription initiation site, one of which is conserved in the respective human gene.

Differential memory and executive functions in demented patients with Parkinson's and Alzheimer's disease.

Selected aspects of verbal memory and executive function were compared in 11 demented Parkinson's disease (PD) patients and 11 Alzheimer's disease (AD) patients with equally severe dementia, with 11 healthy controls matched for age and education. Semantic and episodic memory were impared in all patients compared with controls, but to a relatively greater degree in AD patients than in those with PD. In contrast, demented PD patients were relatively more compromised on executive tasks.

Visuospatial cognition in Huntington's disease.

The notion of specificity of visuospatial dysfunction in Huntington's disease (HD) was evaluated in a sample of afflicted patients as a function of symptom duration, age at onset, and overall dementia severity. Factor analytic procedures indicated that overall visuospatial processing capacity (factor 1) as well as the ability for spatial manipulation (factor 3) was markedly affected in HD patients. In contrast, consistency of spatial judgment (factor 2) appeared to remain relatively intact in these patients.

Subgroups in Alzheimer's disease: fact or fiction?

Alzheimer's disease, which accounts for the majority of all dementing disorders, presents with a wide spectrum of demographic, neuropsychological, pathological and biochemical characteristics. It has become increasingly clear that Alzheimer's disease is indeed heterogeneous and lack of success in symptomatic treatment may be in part related to this. In an attempt to evaluate the utility of possible subgrouping schemas, we reviewed current criteria used to subclassify patients with Alzheimer's disease.

Variations of core-temperature rhythms in unrestrained sheep.

Variations of core-temperature rhythms occurring during a "normal" day (24-hour period without extraordinary challenges for organism) were studied in 5 male sheep. To record the influence of the metabolic processes in different organic systems, core temperatures were measured at various locations at the same time. To minimise any influences due to measurement or behavior (e.

Selective deficits in Alzheimer and parkinsonian dementia: visuospatial function.

Deficits in visuospatial cognition are frequently cited as an important component of the cognitive changes accompanying Parkinson's disease. To characterize possible differences between Parkinson's (PD) and Alzheimer's (AD) dementia, patients from both groups, matched for overall dementia severity, age and education, were contrasted neuropsychologically. Visuospatial tasks dissociated from memory, were significantly compromised in both patient groups.

Selective deficits in cognition and memory in high-functioning parkinsonian patients.

To evaluate the profile and extent of cognitive deficits in Parkinson's disease, afflicted patients of exceptional professional distinction, who continue to function successfully in leadership positions, were compared neuropsychologically to neurologically normal individuals, matched for sex, age, education and professional standing. While patients showed relative preservation of verbal skills and higher executive function, they exhibited a significant reduction in episodic memory and visuospatial function. The observation of circumscribed impairment in this select group of Parkinsonian patients further implicates cognitive and memory deficits as consistent features of Parkinson's disease.