PubMed Health⌕ Search

Biomedical subjects

A D Landman

Publications and source records attributed to A D Landman.

At least 19 recordsLinked to original sources
PubMed2001

Repetitive behaviors in Tourette's syndrome and OCD with and without tics: what are the differences?

Gilles de la Tourette Syndrome (GTS) and obsessive-compulsive disorder (OCD) share obsessive-compulsive phenomena. The aims of this study were to compare the OC symptom distribution between GTS and OCD and to investigate whether a subdivision of these phenomena into obsessions, compulsions and 'impulsions' is useful in distinguishing GTS and OCD patients. Thirty-two GTS, 31 OCD (10 with tics, 21 without tics) and 29 control subjects were studied using the Leiden repetitive behaviors semi-structured interview to assess GTS as well as OCD-related behaviors. Each reported repetitive thought or action was evaluated on the presence of anxiety and on goal-directedness. This information was used to define whether the behavior was an obsession, compulsion, or 'impulsion'. Both the GTS and OCD study groups showed higher scores than control subjects on rating scales measuring depression, OC behavior and anxiety. In GTS, Y-BOCS severity scores and trait anxiety were lower than in the OCD groups. Furthermore, GTS patients differed from OCD patients in the distribution of symptoms. Aggressive repetitive thoughts, contamination worries and washing behaviors were reported more frequently by tic-free OCD, while mental play, echophenomena, touching and (self)-injurious behaviors were reported more frequently by GTS. OCD individuals with tics were intermediate, but closer to tic-free OCD. GTS individuals reported significantly more 'impulsions' and fewer obsessions and compulsions than OCD individuals with and without tics. Factor analysis revealed three factors accounting for 44% of the variance, resulting in an 'impulsive' factor related to GTS, a 'compulsive' factor related to OCD and an 'obsessive' factor related to tic-free OCD. In conclusion, OCD individuals reported more anxiety and goal-directedness associated with their behaviors than did GTS subjects. The distinction between obsessions, compulsions and impulsions is of importance in identifying Tourette-related vs. non-Tourette-related repetitions.

Adult↗
PubMed2001

Gilles de la Tourette's syndrome with and without obsessive-compulsive disorder compared with obsessive-compulsive disorder without tics: which symptoms discriminate?

Stereotyped repetitive behaviors occur in Gilles de la Tourette's Syndrome (GTS) and obsessive-compulsive disorder (OCD). The present study was undertaken to compare the distribution of obsessive-compulsive and Tourette-related impulsive behaviors in GTS with (+) OCD, GTS without (-) OCD, tic-free OCD, and control subjects. Fourteen GTS + OCD, 18 GTS-OCD, 21 OCD-tic, and 29 control subjects were evaluated using a semistructured interview designed to assess GTS and OCD-related repetitive behaviors. Each reported item was evaluated on the presence of anxiety and goal-directedness. This information was subsequently used to define whether the repetitive behavior was an (anxiety-related) obsession or compulsion, or a (non-anxiety-related) OC-like behavior, impulsion. GTS + OCD subjects reported more overall Tourette-related impulsions than OCD-tic subjects, i.e., more mental play, echophenomena, and touching behaviors but similar frequencies of typical obsessive-compulsive behaviors. Further, GTS + OCD subjects exhibited more overall repetitive behaviors than GTS-OCD subjects, i.e., more Tourette-related impulsions as well as more obsessive-compulsive behaviors. The distribution of symptoms is similar in GTS with and without OCD, and differs from tic-free OCD. These differences suggest that GTS with OCD constitutes a form of GTS, not of OCD, although the possibility that GTS + OCD patients constitute a subgroup distinct from GTS and from OCD can not be excluded by this phenomenological study. Specific non-anxiety-related impulsions seem to discriminate between GTS and OCD-tic individuals. These impulsions possibly reflect differences in underlying mechanisms between GTS and OCD-tics.

Adult↗
PubMed2001

Psychopathology and personality characteristics in relation to blood serotonin in Tourette's syndrome and obsessive-compulsive disorder.

Family studies suggest an interrelationship between Gilles de la Tourette Syndrome (GTS) and some forms of obsessive-compulsive disorder (OCD). Some authors consider GTS to be part of a serotonergically mediated cluster of OCD spectrum disorders. The present study was undertaken to compare measures of psychopathology, personality and blood serotonin between GTS and OCD (without tics), and to investigate whether an OCD spectrum hypothesis is supported for GTS. Fifteen GTS without OCD subjects, 21 tic with (+) OCD subjects, 15 OCD without tic subjects and 26 controls (all without serotonergic medication) were evaluated with self-rated and clinician-rated measures of psychopathology and personality. Whole blood serotonin (5-HT) and platelet monoamine oxidase activity (MAO) was measured, and Spearman's correlations were calculated between whole blood 5-HT, MAO and rating scale scores within the entire sample and within subgroups. There were main effects of OCD on anxiety, obsessive-compulsive, neuroticism and extraversion scores. There were main effects of tics on depression, obsessive-compulsive, trait anxiety and neuroticism scores, and on platelet MAO. There were interaction effects on platelet MAO, 5-HT, Yale-Brown Obsessive-Compulsive Rating Scale severity, trait anxiety and Eysenck Personality Questionnaire neuroticism scores. Platelet MAO activity was elevated in tic-free OCD subjects when compared to tic + OCD, GTS without OCD and controls. Whole blood 5-HT was lowered in tic + OCD patients in comparison to GTS without OCD and tic-free OCD subjects. Whole blood 5-HT and obsessive-compulsive severity were negatively correlated within OCD without tic patients and MAO and Leyton Obsessive Inventory scores were negatively related within GTS without OCD patients. The biochemical data of this study suggest that in tic + OCD and in tic-free OCD patients, 5-HT dysregulations play a role, but not necessarily in pure GTS. Serotonergic dysregulations within tic + OCD and tic-free OCD patients are distinct, suggesting differences in underlying pathophysiology. The finding that obsessions and compulsions can be associated with either 5-HT hypofunctionality or hyperfunctionality reveals a major weakness in the OCD spectrum theory, i.e. that the associations between obsessive-compulsive behaviours and 5-HT abnormalities are less specific than suggested by the original obsessive-compulsive spectrum model.

Adult↗
PubMed2000

The relationship between types and severity of repetitive behaviors in Gilles de la Tourette's disorder and obsessive-compulsive disorder.

BACKGROUND: This study investigated which categories of obsessive-compulsive and Tourette-related behaviors in Gilles de la Tourette's disorder and obsessive-compulsive disorder (OCD) without tics are experienced as most severe across the study groups and what the differences are in symptom distribution between the study groups. METHOD: Fourteen subjects with both Tourette's disorder and OCD, 18 subjects with Tourette's only, 21 subjects with OCD (no tics), and 29 control subjects were studied using a semistructured interview designed to equally assess Tourette- and OCD-related behaviors according to DSM-III-R criteria. Each reported repetitive behavior was evaluated on the presence of anxiety and on goal-directedness. Anxiety-related items were categorized as obsessions or compulsions and non-anxiety-related items as impulsions. Severity of each reported item was assessed with respect to time per day consumed and amount of distress and interference induced by the item. Following these criteria, each reported item was classified as a symptom, a subthreshold symptom, or just as being present. RESULTS: Across the study groups, obsessions were experienced as more severe than (Tourette-related) impulsions and compulsions. Within the study groups, patients with both Tourette's disorder and OCD reported more symptomatic Tourette-related impulsions, such as mental play, echophenomena, and impulsive or self-injurious behaviors; less overall symptomatic obsessions; and less symptomatic washing than patients with OCD (no tics). The differences among individuals with Tourette's with or without OCD reflected differences in symptom severity rather than differences in symptom distribution. CONCLUSION: Obsessions are more time consuming, distressing, and interfering than compulsions and impulsions. Furthermore, the symptomatic repetitive behaviors were distributed differently among patients with both Tourette's disorder and OCD and patients with OCD (no tics). Patients with Tourette's and OCD are phenomenologically more similar to Tourette's than to OCD. These differences possibly represent differences in underlying pathophysiology between Tourette's and tic-free OCD.

Adult↗
PubMed1979

Properties of (Mg2 + Ca2+)-ATPase of erythrocyte membranes prepared by different procedures: influence of Mg2+, Ca2+, ATP, and protein activator.

Erythrocyte membranes prepared by three different procedures showed (Mg2+ + Ca2+)-ATPase activities differing in specific activity and in affinity for Ca2+. The (Mg2+ + Ca2+)-ATPase activity of the three preparations was stimulated to different extents by a Ca2+-dependent protein activator isolated from hemolysates. The Ca2+ affinity of the two most active preparations was decreased as the ATP concentration in the assay medium was increased. Lowering the ATP concentration from 2 mM to 2-200 microM or lowering the Mg:ATP ratio to less than one shifted the (Mg2+ + Ca2+)-ATPase activity in stepwise hemolysis membranes from mixed "high" and "low" affinity to a single high Ca2+ affinity. Membranes from which soluble proteins were extracted by EDTA (0.1 mM) in low ionic strength, or membranes prepared by the EDTA (1-10 mM) procedure, did not undergo the shift in the Ca2+ affinity with changes in ATP and MgCl2 concentrations. The EDTA-wash membranes were only weakly activated by the protein activator. It is suggested that the differences in properties of the (Mg2+ + Ca2+)-ATPase prepared by these three procedures reflect differences determined in part by the degree of association of the membrane with a soluble protein activator and changes in the state of the enzyme to a less activatable form.

Adenosine Triphosphatases↗
PubMed1976

Testosterone in human saliva.

Testosterone has been detected in whole human saliva. Levels averaged (+/- SE) 295 +/- 36 and 195 +/- 25 pg/ml in adult males and females, respectively, and usually were undetectable in children. In adult males, the excretion of testosterone in saliva appeared to follow a circadian rhythm.

Adult↗
PubMed1976

A sensitive assay for proteases using a clot timer apparatus.

This report describes the adaptation of milk coagulation by proteases into a quantitative and sensitive assay for these enzymes. The procedure involves the use of a clot timer to determine the precise phase of the coagulation which occurs when buffered milk and a protease interact.

Animals↗
PubMed1975

Acetyl-Coenzyme A carboxylase. Role of the prosthetic group in enzyme polymerization.

Apo-(acetyl-CoA carboxylase) completely free from the holoenzyme was prepared from biotin-deficient rat adipose tissue by using affinity chromatography. The apoenzyme does not aggregate under conditions favouring the transition of the holoenzyme to the polymeric form. Such transition is possible after the conversion of the apoenzyme into the holoenzyme in vitro, thus demonstrating the requirement of the prosthetic biotinyl group for enzyme activation.

Acetyl-CoA Carboxylase↗