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Objective documentation of child abuse and dissociation in 12 murderers with dissociative identity disorder.

OBJECTIVE: The skepticism regarding the existence of dissociative identity disorder as well as the abuse that engenders it persists for lack of objective documentation. This is doubly so for the disorder in murderers because of issues of suspected malingering. This article presents objective verification of both dissociative symptoms and severe abuse during childhood in a series of adult murderers with dissociative identity disorder. METHOD: This study consisted of a review of the clinical records of 11 men and one woman with DSM-IV-defined dissociative identity disorder who had committed murder. Data were gathered from medical, psychiatric, social service, school, military, and prison records and from records of interviews with subjects' family members and others. Handwriting samples were also examined. Data were analyzed qualitatively. RESULTS: Signs and symptoms of dissociative identity disorder in childhood and adulthood were corroborated independently and from several sources in all 12 cases; objective evidence of severe abuse was obtained in 11 cases. The subjects had amnesia for most of the abuse and underreported it. Marked changes in writing style and/or signatures were documented in 10 cases. CONCLUSIONS: This study establishes, once and for all, the linkage between early severe abuse and dissociative identity disorder. Further, the data demonstrate that the disorder can be distinguished from malingering and from other disorders. The study shows that it is possible, with great effort, to obtain objective evidence of both the symptoms of dissociative identity disorder and the abuse that engenders it.

Adult↗

Dissociative tendencies and the sitting duck: are self-reports of dissociation and victimization symptomatic of neuroticism?

Previous research has shown dissociative tendencies are related to a reported history of childhood abuse. A recent study by Johnson, Edman, and Danko (1995) suggested, however, that dissociation may be associated with a more general tendency to recall and report negative life experiences. Johnson and colleagues hypothesized that the relationship between dissociation and self-reported victimization stems from their shared origin as neurotic symptoms. In a test of this hypothesis, Australian adults (N = 92) were administered the Eysenck Personality Questionnaire, the Dissociative Experiences Scale, the Schizotypal Personality Questionnaire-Brief, the Bad Things Scale, and the Childhood Trauma Questionnaire. Hierarchical regression analysis revealed a significant relationship between dissociation and self-reported victimization even after the contribution of neuroticism had been removed. Schizotypy also was found to be a predictor of dissociative tendencies. The hypothesis of Johnson and colleagues was rejected. The findings are discussed in relation to traumagenic models of dissociation.

Adolescent↗

Dissociative experiences and dissociative disorders in acute psychiatric inpatients.

The study attempted to determine the extent of dissociative experiences and the prevalence of dissociative disorders (DDs) in a series of acute psychiatric inpatients and to correlate these experiences and disorders with some sociodemographic, clinical, and historical variables. A total of 207 consecutively admitted psychiatric inpatients qualified for the study. All were examined with the Dissociative Experiences Scale (DES), Structured Clinical Interview for DSM-III-R Personality Questionnaire (SCID-II PQ), Parental Bonding Instrument (PBI), and Frankfurter Self-Concept Scales (FS). Patients who scored greater than 20 on the DES were examined with the Dissociative Disorders interview Schedule (DDIS). Altogether, 20% of patients scored greater than 20 on the DES. In 5% of the patients, a DD was diagnosed. Significant positive correlations were found between DES scores and SCID-II PQ items' frequency with regard to all personality disorder types, especially borderline, antisocial, schizotypal, and dependent. Less pronounced correlations were found between DES and PBI scores, and between DES score and age. Clinical axis I diagnoses did not have any pronounced influence on the DES score. In contrast, patients with greater proneness to dissociation scored lower on most FS scales. There was a tendency for patients with DDs to report childhood abuse more frequently and they complained significantly more of somatic symptoms. Dissociative experiences seem to be as frequent in Swiss as in North American inpatients, whereas DDs (and childhood abuse) were encountered less frequently in Swiss inpatients. A correlation seems to exist between dissociation and somatization.

Acute Disease↗

Use of the Structured Clinical Interview for DSM-IV Dissociative Disorders for systematic assessment of dissociative symptoms in posttraumatic stress disorder.

OBJECTIVE: This study compared dissociative symptom areas in Vietnam combat veterans with posttraumatic stress disorder (PTSD) and in Vietnam combat veterans without PTSD. METHOD: The Structured Clinical Interview for DSM-IV Dissociative Disorders (SCID-D) was used to compare dissociative symptoms in 40 Vietnam combat veterans with PTSD and 15 Vietnam combat veterans without PTSD. The SCID-D yields a total score and scores in five symptom areas: amnesia, depersonalization, derealization, identity confusion, and identity alteration. RESULTS: The PTSD patients had more severe dissociative symptoms in each of the five symptom areas of the SCID-D and higher total symptom scores. Amnesia was the symptom area with the greatest difference in scores between the PTSD patients (mean = 3.68, SD = 0.73) and the non-PTSD veterans (mean = 1.06, SD = 0.26). CONCLUSIONS: The finding of higher levels of dissociative symptoms in Vietnam combat veterans with PTSD than in Vietnam veterans without PTSD is consistent with a level of dissociative symptoms in PTSD similar to that in dissociative disorders.

Adult↗

Development of dissociation: examining the relationship between parenting, maternal trauma and child dissociation.

While many studies have demonstrated relationships between trauma and dissociation, relatively little is known about other factors that may increase children's risk for developing dissociative symptoms. Drawing on betrayal trauma theory and Discrete Behavioral States frameworks, the current study examined the contributions of maternal factors (including mothers' dissociation, betrayal trauma experiences, and inconsistent parenting) to children's dissociation. Seventy-two mother-child dyads completed self-report questionnaires. Maternal dissociation was found to relate positively to maternal betrayal trauma history. Additionally, both mothers' and children's betrayal trauma history were found to significantly predict children's dissociation. Implications for the intergenerational transmission of betrayal trauma and dissociation are discussed.

Adult↗

Electron capture dissociation and infrared multiphoton dissociation MS/MS of an N-glycosylated tryptic peptic to yield complementary sequence information.

Glycoproteins are a functionally important class of biomolecules for which structural elucidation presents a challenge. Fragmentation of N-glycosylated peptides, employing collisionally activated dissociation, typically yields product ions that result from dissociation at glycosidic bonds, with little occurrence of dissociation at peptide backbone sites. We have applied two dissociation techniques, electron capture dissociation (ECD) and infrared multiphoton dissociation (IRMPD), in a 7-T Fourier transform ion cyclotron resonance mass spectrometer, in the investigation of an N-glycosylated peptide from an unfractionated tryptic digest of the lectin of the coral tree, Erythrina corallodendron. ECD provided c and z. ions derived from the peptide backbone, with no observed loss of sugars. Cleavage at 11 of 15 backbone amine bonds was observed. The lack of cleavage at sites located close to the glycosylated asparagine residue may result from steric blocking by the glycan. IRMPD provided abundant fragment ions, primarily through dissociation at glycosidic linkages. The monosaccharide composition and the presence of three glycan branch sites could be determined from the IRMPD fragments. The two types of spectra, obtained with the same instrument, thus provide complementary structural information about the glycopeptide. The current result extends the applicability of ECD for glycopeptide analysis to N-glycosylated peptides and to peptides containing branched, highly substituted glycans.

Electrons↗

Recycling of the hepatic asialoglycoprotein receptor in isolated rat hepatocytes. Receptor-ligand complexes in an intracellular slowly dissociating pool return to the cell surface prior to dissociation.

We recently reported that the dissociation of internalized receptor-125I-asialo-orosomucoid (ASOR) complexes by isolated hepatocytes is a biphasic process; most complexes dissociate rapidly but 25-50% dissociate slowly (Oka, J. A., and Weigel, P. H. J. Biol. Chem. 258, 10253-10262). Cells were allowed to endocytose a pulse of surface-bound 125I-ASOR, and were washed and then incubated at 37 degrees C in the presence or absence of ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA). Without EGTA, very little intact ASOR appeared in the medium. With EGTA present, a large amount of intracellular ligand appeared undegraded in the medium in a time-dependent manner. N-Acetylgalactosamine, but not ASOR, in the medium also caused release of intact 125I-ASOR. Within 15 min, more than 50% and by completion at least 80% of the internalized ligand in the slow dissociation compartment was released into the medium. If cells containing internalized ligand were incubated at 37 degrees C for increasing times before the addition of EGTA, then progressively less ligand accumulated in the medium. Experiments at 18 degrees C, a temperature at which neither degradation nor slow dissociation occurred, demonstrated that in the presence of EGTA the intracellular free 125I-ASOR pool did not change. The amount of receptor-bound ligand in the slowly dissociating pool decreased and the amount of intact ligand in the medium increased by essentially equal amounts. The temperature dependence for the return of internal 125I-ASOR to the cell surface was similar to that for endocytosis, with a cut-off temperature of about 12 degrees C. We conclude that a normal part of the endocytic process involves the return of receptor-ligand complexes to the cell surface from an internal slowly dissociating pool. This might reflect either an obligatory step or a reversible statistically random step in the endocytic/recycling pathway.

Acetylgalactosamine↗

Is dissociation a multidimensional construct? Data from the Multiscale Dissociation Inventory.

The dimensionality of dissociation was examined in a combined sample of 1,326 general population, clinical, and university participants who completed the Multiscale Dissociation Inventory (MDI). Principal components analysis identified five moderately intercorrelated factors (mean r = .39): Disengagement, Identity Dissociation, Emotional Constriction, Memory Disturbance, and Depersonalization/Derealization. Differential relationships were found between individual MDI factors and demographics, trauma history, clinical status, posttraumatic stress, and scores on other dissociation measures. Surprisingly, after controlling for sex and age, trauma exposure accounted for only 3 to 7% of the variance in MDI factors. The notion of dissociation as a general trait was not supported. Instead, dissociation may represent a variety of phenomenologically distinct and only moderately related symptom clusters whose ultimate commonality is more theoretical than empirical.

Adolescent↗

The development of the somatoform dissociation questionnaire (SDQ-5) as a screening instrument for dissociative disorders.

Using cases of dissociative disorder (n=50) and other DSM-IV diagnoses (n=50), a somatoform dissociation self-report questionnaire was developed and its capacity to function as a screening device for dissociative disorders was analysed. A list of 75 items was constructed which, according to clinical experience and expert judgement, could reflect instances of somatoform dissociation. Statistical analyses revealed the 20 best discriminating items. Stepwise forward logistic analysis detected five items which, as a group, provided optimal discrimination between the two groups. At an estimated prevalence rate of dissociative disorders of 10% among psychiatric patients the sensitivity would be 94%, the specificity would be 96%, the positive predictive value would be 72%, and the negative predictive value would be 99%. Cross-validation in an independent sample (n=33/42) largely corroborated the initial findings. The SDQ-5 can be used as a brief screening device for dissociative disorders.

Adolescent↗

The North Carolina Dissociation Index: a measure of dissociation using items from the MMPI-2.

The development of a new measure of dissociation using items from the Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) is described. In Experiment 1, 525 college students were administered a measure of hypnotic susceptibility and completed several specialized measures of dissociation or dissociation-like experiences. The new measure, the North Carolina Dissociation Index (NCDI) demonstrated adequate internal consistency and good convergent validity. In Experiment 2, the NCDI demonstrated adequate internal consistency and test-retest reliability with a different sample of college students. Moreover, NCDI scores showed a relatively strong correlation with an interview-based measure of dissociative symptoms. In addition, a small sample of students with dissociative disorders had significantly higher NCDI scores than students with anxiety disorders and normal control subjects. In Experiment 3, 19 gang combat veterans were administered a semistructured diagnostic interview and the MMPI-2. Subjects who were diagnosed with Posttraumatic Stress Disorder (PTSD) scored significantly higher on the NCDI than subjects who did not have PTSD. The NCDI is intended primarily as a tool in settings where the MMPI-2 is routinely administered.

Adolescent↗

Dissociation kinetics of the thyrotropin-receptor complex. Characterization of a slowly dissociable component.

The kinetics of the dissociation of thyrotropin (TSH) from human thyroid plasma membranes were studied in an attempt to further understand the molecular dynamics of the TSH--receptor interaction. Dissociation of bound [125I]TSH from thyroid plasma membranes was a biphasic process consisting of rapidly and slowly dissociable components, RDC and SDC, respectively. The dilution induced dissociation of bound [125I]TSH was enhanced by the addition of excess TSH (DEC). DEC was proportional to the dose of unlabeled TSH and its magnitude increased linearly with temperature. These results are in contrast to those reported for the kinetics of [125I]insulin dissociation. The functional significance of DEC remains largely unexplained. It was found that the fraction of SDC was dependent upon time of association in a temperature-dependent and apparently saturable process. It could not be attributed to alterations in the electrophoretic, immunologic or binding properties of [125I]TSH. Furthermore, no correlation was observed between generation of SDC and change in the Scatchard profile of TSH binding, in contrast to studies on growth hormone. These data suggest that, like some other polypeptide hormones, binding of TSH to its receptor does not proceed according to laws describing simple, rapidly reversible, bimolecular reactions. Furthermore, bound TSH undergoes a receptor-mediated conversion from a rapidly to a slowly dissociable state with time of incubation.

Animals↗

Dissociation energetics and mechanisms of leucine enkephalin (M + H)+ and (2M + X)+ ions (X = H, Li, Na, K, and Rb) measured by blackbody infrared radiative dissociation.

The dissociation kinetics of protonated leucine enkephalin and its proton and alkali metal bound dimers were investigated by blackbody infrared radiative dissociation in a Fourier-transform mass spectrometer. From the temperature dependence of the unimolecular dissociation rate constants, Arrhenius activation parameters in the zero-pressure limit are obtained. Protonated leucine enkephalin dissociates to form b(4) and (M-H(2)O)(+) ions with an average activation energy (E(a)) of 1.1 eV and an A factor of 10(10.5) s(-1). The value of the A factor indicates that these dissociation processes are rearrangements. The b(4) ions subsequently dissociate to form a(4) ions via a process with a relatively high activation energy (1.3 eV), but one that is entropically favored. For the cationized dimers, the thermal stability decreases with increasing cation size, consistent with a simple electrostatic interaction in these noncovalent ion-molecule complexes. The E(a) and A factors are indistinguishable within experimental error with values of approximately 1.5 eV and 10(17) s(-1), respectively. Although not conclusive, results from master equation modeling indicate that all these BIRD processes, except for b(4) --> a(4), are in the rapid energy exchange limit. In this limit, the internal energy of the precursor ion population is given by a Boltzmann distribution and information about the energetics and dynamics of the reaction are obtained directly from the measured Arrhenius parameters.

Journal Article↗

Dissociation of Ca2+ from sarcoplasmic reticulum Ca2+-ATPase and changes in fluorescence of optically selected Trp residues. Effects of KCl and NaCl and implications for substeps in Ca2+ dissociation.

Sequential dissociation of the two Ca2+ ions bound to non-phosphorylated sarcoplasmic reticulum Ca2+-ATPase was triggered by addition, in a stopped-flow experiment, of quin2, which acted both as a high-affinity chelator and as a Ca2+-sensitive fluorescent probe. The kinetics of Ca2+ dissociation were deduced from the observed changes in quin2 fluorescence in the visible region (with lambdaex = 313 nm), while fluorescence detection in the UV region (with lambdaex = 290 nm) made it possible to monitor the tryptophan fluorescence changes accompanying this dissociation under the same ionic conditions. In the absence of KCl or NaCl, at pH 6 or 7, the observed changes in quin2 fluorescence were monoexponential, with rate constants very close to those of the changes in ATPase tryptophan fluorescence, which also appeared monophasic. In the presence of 100 mM KCl, quin2 fluorescence changes, although still monoexponential, were faster than in the absence of the monovalent ions but distinctly slower than the changes in tryptophan fluorescence, which were accelerated to a larger extent. In addition, the apparent kinetics of the Trp fluorescence changes depended on the excitation wavelength. Using an excitation wavelength of 296 nm, the Trp fluorescence drop was still faster than with an excitation wavelength of 290 nm, and in the presence of NaCl it even displayed a clear undershoot. We conclude that in the presence of KCl or NaCl and with an excitation wavelength of 290 nm, the rapid drop in tryptophan fluorescence mainly monitors the dissociation of the first of the two Ca2+ ions to be released from Ca2+-ATPase, while excitation at 296 nm optically selects a subpopulation of Trp residues whose fluorescence level is lower in the ATPase species with one Ca2+ ion bound than in the Ca2+-deprived ATPase species. The latter conditions result in an initial drop in Trp fluorescence whose apparent rate constant (in single-exponential analysis) is faster than the true rate of dissociation of the first Ca2+ ion and in a subsequent slower rise related to dissociation of the second Ca2+ ion. The difference between results obtained in the absence and in the presence of K+ or Na+ is due to an antagonizing effect of these cations on proton-induced conformational rearrangement of Ca2+-free ATPase, a conformational rearrangement which changes the ATPase Trp fluorescence level and significantly affects the cooperativity of Ca2+ binding at equilibrium.

Aminoquinolines↗

N[bond]C(alpha) bond dissociation energies and kinetics in amide and peptide radicals. Is the dissociation a non-ergodic process?

Dissociations of aminoketyl radicals and cation radicals derived from beta-alanine N-methylamide, N-acetyl-1,2-diaminoethane, N(alpha)-acetyl lysine amide, and N(alpha)-glycyl glycine amide are investigated by combined density functional theory and Møller-Plesset perturbational calculations with the goal of elucidating the mechanism of electron capture dissociation (ECD) of larger peptide and protein ions. The activation energies for dissociations of N[bond]C bonds in aminoketyl radicals decrease in the series N[bond]CH(3) > N-CH(2)CH(2)NH(2) >> N[bond]CH(2)CONH(2) approximately N[bond]CH(CONH(2))(CH(2))(4)NH(2). Transition state theory rate constants for dissociations of N[bond]C(alpha) bonds in aminoketyl radicals and cation-radicals indicate an extremely facile reaction that occurs with unimolecular rate constants >10(5) s(-1) in species thermalized at 298 K in the gas phase. In neutral aminoketyl radicals the N[bond]C(alpha) bond cleavage results in fast dissociation. In contrast, N[bond]C(alpha) bond cleavage in aminoketyl cation-radicals results in isomerization to ion-molecule complexes that are held together by strong hydrogen bonds. The facile N[bond]C(alpha) bond dissociation in thermalized ions indicates that it is unnecessary to invoke the hypothesis of non-ergodic behavior for ECD intermediates.

Alanine↗

Elastase +/- soybean trypsin inhibitor dissociation of rat oral mucosa: ultrastructural and oxidative metabolic destructive changes in isolated, epithelial and dermal mitochondria after dissociation.

Epithelial and connective tissue compartments of rat oral mucosa were dissociated after incubation with elastase +/- soybean trypsin inhibitor (SBTI). Elastase + SBTI induced greater ultrastructural damage within the dissociated compartments than elastase alone. The basal lamina remained with the epithelial layer after elastase separation and was destroyed after exposure to elastase + SBTI. Isolated epithelial mitochondria were more severely damaged ultrastructurally after elastase + SBTI separation of the compartment than those prepared after exposure to elastase alone. Isolated fibroblast mitochondria were damage to the same extent after dissociation of the compartment with either medium. Oxidative metabolism and mitochondrial recoveries declined significantly after exposure to either dissociating medium. Cytochrome oxidase activity was significantly greater than succinic cytochrome c reductase in the control and experimental groups. Oxidative metabolism was found to be significantly greater in the connective tissue compartment than the epithelial compartment after dissociation of immature rat oral mucosa. Our data suggests that caution be utilized in assessing cellular viability and oxidative metabolism in tissue compartments immediately after their dissociation by proteolytic enzymes.

Animals↗

Measurement of dissociative states with the Clinician-Administered Dissociative States Scale (CADSS).

The purpose of this study was to develop an instrument for the measurement of present-state dissociative symptoms, the Clinician Administered Dissociative States Scale (CADSS). Reported here are interrater reliability and internal consistency of the CADSS, validity as assessed by comparisons with other instruments for the assessment of dissociation, and sensitivity of the CADSS to discriminate patients with dissociative disorders from patients with other psychiatric disorders and healthy subjects. Initial analyses indicated good interrater reliability and construct validity for the CADSS. Scores on the CADSS discriminated patients with dissociative disorders from the other groups.

Adult↗

Dissociative tendencies and dissociative disorders.

Although dissociative disorders are relatively rare, dissociative experiences are rather common in everyday life. Dissociative tendencies appear to be modestly related to other dimensions of personality, such as hypnotizability, absorption, fantasy proneness, and some facets of openness to experience. These dispositional variables may constitute diathesis, or risk factors, for dissociative psychopathology, but more complex models relating personality to psychopathology may be more appropriate. The dissociative disorders raise fundamental questions about the nature of self and identity and the role of consciousness and autobiographical memory in the continuity of personality.

Dissociative Disorders↗