Diphenylhydantoin, Phenobarbital, and Primidone in Saliva, Plasma, and Cerebrospinal Fluid

Diphenylhydantoin, primidone, and phenobarbital were determined in saliva and plasma of 164 patients by gas-liquid chromatography. The saliva ratio was about one-tenth in patients on diphenylhydantoin, 0.32-0.38 on phenobarbital alone and with other drugs, 0.97 and 0.96 on primidone alone and with other drugs. The S/P ratio of phenobarbital was similar in patients treated with primidone alone or with co-medication. For diphenylhydantoin and primidone, the S/P and CSF/plasma ratio were similar; for phenobarbital the S/P ratio was lower due to the difference in pH of saliva and CSF. Thus the concentration in saliva serves as a measure of the nonprotein-bound or free concentration in plasma with the advantage that saliva is easy to obtain. Co-medication does not change the S/P ratio for the three drugs studied. The high correlation between levels in plasma and in saliva allows the plasma levels to be predicted from the concentration in saliva.     

Fasciitis, perimyositis, myositis, polymyositis, and eosinophilia

Several groups of cases of fasciitis and myositis with eosinophilia are reported. The common features are inflammation into fascia and/or perimysium, and/or muscle fibers; eosinophilia in blood and/or in muscle biopsy. The following classification of 24 cases is suggested: at one end of the spectrum are fasciitis with eosinophilia: diffuse fasciitis (Shulman syndrome): 10 cases (3 with hematological complications); 2 cases of diffuse fasciitis with muscle atrophy; 3 cases of restricted fasciitis. Relapsing perimyositis with eosinophilia belong to the same spectrum, either diffuse (5 cases) with myalgias, or localized (2 cases). Other cases are focal myositis or multiple myositis, polymyositis with eosinophilia. The relationship among these cases is discussed. There is a continuum among the different groups. The pathophysiology remains unknown.     

Caspases, apoptosis, and Alzheimer disease: causation, correlation, and confusion

Extensive neuron loss occurs in Alzheimer disease (AD) brain and some authors have speculated that dysregulation of apoptotic death pathways is etiologically responsible for the disease. Apoptosis is regulated in mammalian cells by a family of cysteine proteases called caspases. At least 7 different caspases (caspases 1, 2, 3, 6, 8, 9, and 12) have been implicated in regulating neuronal cell death in response to amyloid beta (A beta) exposure in vitro, in animal models of neurodegenerative diseases, and in AD brain itself. Despite this seemingly impressive array of data implicating caspases and apoptosis as etiologic factors in AD, the direct involvement of caspase-dependent neuronal apoptosis in AD pathogenesis remains uncertain. Alternative explanations for some findings, contradictory experimental observations, and lack of morphologically convincing apoptotic neurons in the vast majority of AD brains has led to the revised hypothesis that apoptosis-associated molecular events cause neuronal dysfunction in the absence of, or prior to, neuronal death. Unfortunately, this new view renders the term "apoptosis-associated" functionally meaningless since it bears no relationship with apoptotic death and fails to focus scientific investigation on the molecular insults that trigger the "apoptosis-associated" response in AD neurons. On balance, an etiologic role for caspases in AD is far from proven. It remains possible, however, that caspase-dependent neuronal death contributes to AD neuron loss and thus, caspase inhibition offers some hope for extending AD neuron survival so that other agents, targeting upstream events, may delay or reverse primary AD pathology.     

Locked-in Syndrome,BCI, and a Confusion about Embodied,Embedded, Extended,and Enacted Cognition

In a recent contribution to this journal, Andrew Fenton and Sheri Alpert have argued that the so-called “extended mind hypothesis” allows us to understand why Brain Computer Interfaces (BCIs) have the potential to change the self of patients suffering from Locked-in syndrome (LIS) by extending their minds beyond their bodies. I deny that this can shed any light on the theoretical, or philosophical, underpinnings of BCIs as a tool for enabling communication with, or bodily action by, patients with LIS: BCIs are not a case of cognitive extension. I argue that Fenton and Alpert’s claim to the contrary is the result of a widespread confusion about some related, but significantly different, approaches to cognition that all fall under the heading of “situated cognition.” I first provide a short taxonomy of various situated approaches to cognition, highlighting (some of) their important commonalities and differences, which should dissolve some of the confusions surrounding them. Then I show why the extended mind hypothesis is unsuitable as a model of BCI enhancements of LIS patients’ capacity to interact with their surroundings, and I argue that the situated approach with obvious bearings on the sort of questions that were driving Fenton and Alpert is not the idea that cognition is extended, but the idea that cognition is enacted.     

Sensation seeking,puberty, and nicotine,alcohol, and marijuana use in adolescence

OBJECTIVE: To examine the relationship among nicotine, alcohol, and marijuana use; level of sensation seeking (SS); and pubertal development. METHOD: Subjects were early and middle adolescent males and females recruited from a psychiatric clinic (n = 77) and two general pediatric clinics (n = 131). SS was measured by using the Sensation Seeking Scale for Children. Pubertal development was measured with a modified Pubertal Development Scale that was completed by the adolescent and his/her parent about the adolescent. Adolescent self-reports of nicotine, alcohol, and marijuana use were also obtained using questionnaires. RESULTS: SS was higher in males and females who reported nicotine and alcohol use and in males who reported marijuana use. SS was positively associated with pubertal development in males and females, even when controlling for age. Furthermore, SS mediated the relationship of pubertal development and drug use in males and females. CONCLUSIONS: The observation that SS mediates the relationship between pubertal development and drug use in males and females may contribute to understanding changes in drug use that are seen during adolescence. In addition, SS is associated with drug use and is easily measured in a variety of clinical settings.     

Head size and intelligence, learning, nutritional status and brain development. Head, IQ, learning, nutrition and brain

This multifactorial study investigates the interrelationships between head circumference (HC) and intellectual quotient (IQ), learning, nutritional status and brain development in Chilean school-age children graduating from high school, of both sexes and with high and low IQ and socio-economic strata (SES). The sample consisted of 96 right-handed healthy students (mean age 18.0 +/- 0.9 years) born at term. HC was measured both in the children and their parents and was expressed as Z-score (Z-HC). In children, IQ was determined by means of the Wechsler Intelligence Scale for Adults-Revised (WAIS-R), scholastic achievement (SA) through the standard Spanish language and mathematics tests and the academic aptitude test (AAT) score, nutritional status was assessed through anthropometric indicators, brain development was determined by magnetic resonance imaging (MRI) and SES applying the Graffar modified method. Results showed that microcephalic children (Z-HC < or = 2 S.D.) had significantly lower values mainly for brain volume (BV), parental Z-HC, IQ, SA, AAT, birth length (BL) and a significantly higher incidence of undernutrition in the first year of life compared with their macrocephalic peers (Z-HC > 2S.D.). Multiple regression analysis revealed that BV, parental Z-HC and BL were the independent variables with the greatest explanatory power for child's Z-HC variance (r(2) = 0.727). These findings confirm the hypothesis formulated in this study: (1) independently of age, sex and SES, brain parameters, parental HC and prenatal nutritional indicators are the most important independent variables that determine HC and (2) microcephalic children present multiple disorders not only related to BV but also to IQ, SA and nutritional background.     

Epilepsy and anxiety: epidemiology, classification, aetiology, and treatment

Anxiety in epilepsy has recently become a focus of interest for a number of reasons. Epidemiological studies have established that anxiety disorders are twice as common in patients with epilepsy compared to the general population, while in referral centres their prevalence is even higher. In addition, it has been recently appreciated that anxiety exerts a significant negative impact on the quality of life of patients with epilepsy of any age. With regard to the pathogenesis of anxiety in epilepsy, a number of theories have been put forward including those based on psychodynamics, learning-cognition, and neurobiology. From a clinical point of view, anxiety may occur as a comorbid disorder with epilepsy or be directly linked with epilepsy as a preictal, ictal, postictal or interictal phenomenon. The treatment of anxiety in patients with epilepsy requires a comprehensive, multidisciplinary, clinical assessment. Regarding pharmacological therapies, it should be recognised that some drugs prescribed for anxiety disorders are associated with a high risk of seizures, whereas some antiepileptic drugs possess anxiolytic properties that could be of use in the management of epileptic patients with anxiety. The correct diagnosis and successful treatment of anxiety is expected to have significant benefits for the quality of life of epileptic patients.