The effects of Alzheimer disease on driving-related abilities

Ten Alzheimer disease (AD) patients and 12 healthy elderly controls were evaluated on two tests of driving-related abilities: the Driver Performance Test (DPT) and the Driving Advisement System (DAS). Subjects were administered a battery of neuropsychological tests to determine if severity of dementia in AD correlates with driving performance. On the DPT, the AD patients scored in the average range in two of five skill areas (predicting the effects of a hazard, deciding how to avoid it); below average in two areas (searching for a hazard, executing evasive actions); and poorly in one area (identifying hazards). The elderly controls scored at an average level in all five skill areas. On the DAS, AD patients were significantly slower than the elderly controls on simple, two-choice, and conditional reaction time tests and were much slower than drivers in general. The AD patients' performances on two cognitive tests, the Mini-Mental State Examination (MMSE) and the Category Fluency Test, correlated significantly with aspects of performance on the DPT and the DAS. Although these are preliminary results from a pilot investigation, they suggest that AD patients' driving-related abilities are adversely affected by the disease and that driving-related performance tests and neuropsychological tests may be useful in assessing the impact of AD on driving.     

The prion diseases

The human prion diseases are fatal neurodegenerative maladies that may present as sporadic, genetic, or infectious illnesses. The sporadic form is called Creutzfeldt-Jakob disease (CJD) while the inherited disorders are called familial (f) CJD, Gerstmann-Straussler-Scheinker (GSS) disease and fatal familial insomnia (FFI). Prions are transmissible particles that are devoid of nucleic acid and seem to be composed exclusively of a modified protein (PrPSc). The normal, cellular PrP (PrPC) is converted into PrPSc through a posttranslational process during which it acquires a high beta-sheet content. In fCJD, GSS, and FFI, mutations in the PrP gene located on the short arm of chromosome 20 are the cause of disease. Considerable evidence argues that the prion diseases are disorders of protein conformation.     

The genetics of Alzheimer disease: current status and future prospects

BACKGROUND: Laparoscopic hysterectomy and lymph node dissection have lately been reported as an alternative to an abdominal open procedure for the treatment of malignant gynaecological conditions. The laparoscopic operative technique has been evaluated and compared as to whether it is a safe, feasible and effective procedure. SUBJECTS: The study includes 78 women with indications for surgery for endometrial cancer stage I. A retrospective comparative study was undertaken at Baby Friendly Hospital, Kladno, in which 11 patients treated laparoscopically were compared with 26 patients treated by the open procedure of lymphadenectomy. We evaluated differences in the peri-and postoperative outcomes. RESULTS: All 11 procedures were successfully completed. The mean operating time was 153 min, and mean blood loss was 130 ml. The median hospital stay was 4.7 days. There were no major complications. CONCLUSIONS: Laparoscopic hysterectomy and lymphadenectomy seem to be the procedures which result in a shorter hospital stay and rapid recovery. This approach could potentially decrease morbidity historically associated with hysterectomy and lymphadenectomy performed abdominally. Only prospective randomised studies will be able to demonstrate the ability of operative laparoscopy to improve contemporary management of endometrial cancer.     

The efficacy of Ginkgo biloba on cognitive function in Alzheimer disease

OBJECTIVE: To determine the effect of treatment with Ginkgo biloba extract on objective measures of cognitive function in patients with Alzheimer disease (AD) based on formal review of the current literature. METHODS: An attempt was made to identify all English and non-English-language articles in which G. biloba extract was given to subjects with dementia or cognitive impairment. Inclusion criteria for the meta-analysis were (1) sufficiently characterized patients such that it was clearly stated there was a diagnosis of AD by either Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition, or National Institute of Neurological Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, or there was enough clinical detail to determine this by our review; (2) clearly stated study exclusion criteria, ie, those studies that did not have stated exclusions for depression, other neurologic disease, and central nervous system-active medications were excluded; (3) use of standardized ginkgo extract in any stated dose; (4) randomized, placebo-controlled and double-blind study design; (5) at least 1 outcome measure was an objective assessment of cognitive function; and (6) sufficient statistical information to allow for meta-analysis. RESULTS: Of more than 50 articles identified, the overwhelming majority did not meet inclusion criteria, primarily because of lack of clear diagnoses of dementia and AD. Only 4 studies met all inclusion criteria. In total there were 212 subjects in each of the placebo and ginkgo treatment groups. Overall there was a significant effect size of 0.40 (P<.0001). This modest effect size translated into a 3% difference in the Alzheimer Disease Assessment Scale-cognitive subtest. CONCLUSIONS: Based on a quantitative analysis of the literature there is a small but significant effect of 3- to 6-month treatment with 120 to 240 mg of G. biloba extract on objective measures of cognitive function in AD. The drug has not had significant adverse effects in formal clinical trials but there are 2 case reports of bleeding complications. In AD, there are limited and inconsistent data that preclude determining if there are effects on noncognitive behavioral and functional measures as well as on clinician's global rating scales. Further research in the area will need to determine if there are functional improvements and to determine the best dosage. Additional research will be needed to define which ingredients in the ginkgo extract are producing its effect in individuals with AD.     

Progression of Alzheimer histopathological changes

OBJECTIVE: To describe the morphology of the pulmonary arteries in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries with and without monosomy 22q11. DESIGN: A retrospective analysis of all patients with this congenital heart defect who are being followed at the University Children's Hospital Erlangen. SETTING: A tertiary referral centre for paediatric cardiology and paediatric cardiac surgery. PATIENTS: 21 patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries. Monosomy 22q11 was diagnosed by fluorescent in situ hybridisation using the D22S75 probe (Oncor). The morphology of the pulmonary arteries was assessed on the basis of selective angiograms. RESULTS: 10 patients (48%) were shown to have a microdeletion in 22q11 (group I). There was no difference with respect to the presence of confluent central pulmonary arteries between these patients (80%) and the remaining 11 patients (group II) without monosomy 22q11 (91%). Patients of group I, however, more often had arborisation anomalies of the pulmonary vascular bed (90% in group I v 27% in group II). Because of the more severe abnormalities of the pulmonary arteries, a biventricular repair had not been possible in any of the children with monosomy 22q11, though repair had been carried out in 64% of the children in group II. CONCLUSION: The developmental disturbance caused by the monosomy 22q11 seems to impair the connection of the peripheral pulmonary artery segments to the central pulmonary arteries in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries, resulting in a lower probability of biventricular repair.     

The chronopharmacotherapy of diseases]

Peroperative cholangiography (POC) performed as a routine during cholecystectomy for cholelithiasis was evaluated in 102 patients. POC was normal 93 patients. Nine patients had abnormal POCs: 5 were true positive--CBD stones (4) and sphincteric fibrosis (1): 4 were false positive--air bubbles (2) and sphincteric spasm (2). Preoperative indication of CBD stones were present in 12 patients-5 of these had abnormal POC (4 true positive and 1 false positive). CBD exploration was avoided in 7 patients with normal POC. Ninety patients did not have any preoperative indication of CBD stones-4 of these had abnormal POC (1 true positive and 3 false positive). None of the patients with a normal POC had any clinical evidence of residual stones on follow up for one year. POC did not help in any case to delineate biliary ductal anatomy. Routine POC during cholecystectomy should be abandoned and should be performed selectively in patients suspected to have CBD stones only to avoid a negative CBD exploration.     

From molecular structure to Alzheimer therapy

Clinical trials in the USA, Japan and Europe have confirmed the hypothesis that a steady state increase of acetylcholine resulting from cholinesterase inhibition in the brain results in an improvement of cognitive function in mild to moderate Alzheimer disease (AD) patients. During the last decade, a systematic effort to develop a pharmacological treatment for AD has resulted in two drugs being registered for the first time in the USA and Europe for this specific indication. Both are cholinesterase inhibitors (ChEI). Based on these first positive results, several second generation ChEI are being developed. An additional effect of certain ChEI is to maintain cognitive function at a constant level during a 6 months to one year period of treatment as compared to placebo. It is possible that the drug effect is one of slowing down cognitive deterioration. Comparison of clinical effects of 5 ChEI demonstrates a rather similar magnitude of improvement. For some drugs, this may represent a limit, while for others it may be possible to increase the benefit further. To maximize and prolong positive drug effects, it is important to start early and adjust the dosage during the treatment. Other strategies may involve combinations with other cholinergic drugs such as muscarinic or nicotinic agonists. A second important class of drugs which is being developed is that of muscarinic m1 agonists. However, their clinical use is still limited by side effects. The increased knowledge and recognition of the beta-amyloid molecule as a central focus of AD pathology has strongly stimulated research with the hope of finding ways of influencing its processing and deposition. At this point, no product in this line of development has reached clinical trial level. Other pharmacological approaches are related to preventive and neuroprotective interventions (estrogens, anti-oxidants and anti-inflammatories). In conclusion, given the relatively short time of research in this field, results are encouraging.     

Inhibition of Alzheimer beta-fibrillogenesis by melatonin

It is generally postulated that the amyloid beta protein (Abeta) plays a central role in the progressive neurodegeneration observed in Alzheimer's disease. Important pathologic properties of this protein, such as neurotoxicity and resistance to proteolytic degradation, depend on the ability of Abeta to form beta-sheet structures or amyloid fibrils. We report that melatonin, a hormone recently found to protect neurons against Abeta toxicity, interacts with Abeta1-40 and Abeta1-42 and inhibits the progressive formation of beta-sheets and amyloid fibrils. These interactions between melatonin and the amyloid peptides were demonstrated by circular dichroism and electron microscopy for Abeta1-40 and Abeta1-42 and by nuclear magnetic resonance spectroscopy for Abeta1-40. Inhibition of beta-sheets and fibrils could not be accomplished in control experiments when a free radical scavenger or a melatonin analog were substituted for melatonin under otherwise identical conditions. In sharp contrast with conventional anti-oxidants and available anti-amyloidogenic compounds, melatonin crosses the blood-brain barrier, is relatively devoid of toxicity, and constitutes a potential new therapeutic agent in Alzheimer's disease.     

Amyloid beta protein and Alzheimer disease

Amyloid beta protein is predominant in senile plaques, the neuropathologic hallmarks of Alzheimer disease. Researchers in Winnipeg have shown that this protein can overstimulate certain hydrolytic enzymes to break down the phospholipid building blocks of the brain-cell wall. They speculate that the abnormal destruction of phospholipids gradually drains the energy resources a neuron uses to rebuild its membrane. As neurons "burn out," the brain loses its ability to function normally. In view of evidence that NSAID therapy may interfere with the hydrolysis of phospholipids, the researchers will focus on finding an NSAID-related compound effective against Alzheimer disease.     

Brain infarction and the clinical expression of Alzheimer disease. The Nun Study

OBJECTIVE: To determine the relationship of brain infarction to the clinical expression of Alzheimer disease (AD). DESIGN: Cognitive function and the prevalence of dementia were determined for participants in the Nun Study who later died. At autopsy, lacunar and larger brain infarcts were identified, and senile plaques and neurofibrillary tangles in the neocortex were quantitated. Participants with abundant senile plaques and some neurofibrillary tangles in the neocortex were classified as having met the neuropathologic criteria for AD. SETTING: Convents in the Midwestern, Eastern, and Southern United States. PARTICIPANTS: A total of 102 college-educated women aged 76 to 100 years. MAIN OUTCOME MEASURES: Cognitive function assessed by standard tests and dementia and AD assessed by clinical and neuropathologic criteria. RESULTS: Among 61 participants who met the neuropathologic criteria for AD, those with brain infarcts had poorer cognitive function and a higher prevalence of dementia than those without infarcts. Participants with lacunar infarcts in the basal ganglia, thalamus, or deep white matter had an especially high prevalence of dementia, compared with those without infarcts (the odds ratio [OR] for dementia was 20.7, 95% confidence interval [95% CI], 1.5-288.0). Fewer neuropathologic lesions of AD appeared to result in dementia in those with lacunar infarcts in the basal ganglia, thalamus, or deep white matter than in those without infarcts. In contrast, among 41 participants who did not meet the neuropathologic criteria for AD, brain infarcts were only weakly associated with poor cognitive function and dementia. Among all 102 participants, atherosclerosis of the circle of Willis was strongly associated with lacunar and large brain infarcts. CONCLUSION: These findings suggest that cerebrovascular disease may play an important role in determining the presence and severity of the clinical symptoms of AD.