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A method for dissociation of viable human breast cancer cells that produces flow cytometric kinetic information similar to that obtained by thymidine labeling.

Collagenase dissociation, performed on 40 human breast cancers, yielded between 1 million and 50 million cells from less than 1 g of tissue from each tumor. Approximately 60% of cells (mean) was considered viable as judged by trypan blue exclusion and phase microscopy. On subsequent flow cytometric analysis, 20 cancers (50%) were considered diploid, three were tetraploid, and the remainder, hyperdiploid. Thymidine labeling (TLI) and flow cytometry following mechanical dissociation also were performed on 23 of these 40 tumors. Among this group of 23 cases, the median percentage of S-phase cells obtained by collagenase dissociation was 5.4, by TLI was 5.7, and by mechanical dissociation was 9.7. There was excellent correlation between the percentage of S-phase cells obtained by collagenase and TLI (r = 0.847, p = 0.0001) but only fair correlation between the percentage of S-phase cells obtained by mechanical dissociation and TLI (r = 0.597, p = 0.0027). The percentage of S-phase cells obtained by either collagenase or mechanical dissociation predicted whether a tumor was above or below median TLI in 19 of 23 cases (p = 0.0018). Estrogen receptor positivity or negativity did not predict whether a tumor was above or below median TLI (r = 0.283, p = 0.130) or above or below median S-phase fraction following collagenase dissociation (r = 0.218, p = 0.182), nor did quantitative estrogen receptor correlate significantly with TLI (r = 0.283, p = 0.13) or S-phase fraction (r = 0.218, p = 0.18).

Breast Neoplasms↗

Dissociative thermal inactivation, stability, and activity of oligomeric enzymes.

Results of kinetic studies on dissociative thermal inactivation of oligomeric enzymes are discussed. Dissociative thermal inactivation is the process in which the kinetically irreversible protein change is preceded by a reversible stage of oligomer dissociation. In experiments, this is demonstrated by the dependence of inactivation rate on total protein concentration. This paper gives the relations which allow the calculation from experimental data the following physicochemical constants which characterize the stability of oligomeric enzymes: the constant for the rate of irreversible change of monomeric protein, the equilibrium constant for dimer dissociation, and the rate constant for dimer dissociation. The problem of a "conformational lock", the contact between protein globules that admits a multistep destruction of active oligomer and explains the induction period occurring in kinetic thermal inactivation curves, is discussed. The X-ray structural analyses for several dimeric enzymes, i.e., alkaline phosphatase (EC 3.1.3.1) from E. coli, alcohol dehydrogenase (EC 1.1.1.1) from horse liver, and baker's yeast enolase (EC 4.2.1.11), explain why they lose catalytic activity during the dissociation of the protein into monomers and also provide a physically reasonable picture of the structure of their conformational lock. Also, these data support the kinetic scheme used to describe the dissociative inactivation of dimeric enzymes.

Alcohol Dehydrogenase↗

Dissociative detachment relates to psychotic symptoms and personality decompensation.

Previous studies have addressed the prominence of psychotic symptoms in conjunction with multiple personality disorder (now dissociative identity disorder). The present study examines the relation between psychotic symptoms and a more pervasive form of dissociative disturbance, namely dissociative detachment. Two hundred sixty-six women in inpatient treatment for severe trauma-related disorders completed the Dissociative Experiences Scale (DES), and 102 of these patients also completed the Millon Clinical Multiaxial Inventory (MCMI-III). A factor analysis of the DES yielded two dimensions of dissociative detachment: detachment from one's own actions and detachment from the self and the environment. Each of these DES dimensions relates strongly to the thought disorder and schizotypal personality disorder scales of the MCMI-III. We propose that severe dissociative detachment, by virtue of loosening the moorings in inner and outer reality, is conducive to psychotic symptoms and personality decompensation.

Adult↗

The diagnosis of multiple personality disorder based on subtle dissociative signs.

Patients with multiple personality disorder (MPD) often present with subtle dissociative signs and symptoms rather than with the clear-cut, overt dissociative signs and symptoms usually associated with MPD. Because most MPD patients usually conceal their condition, there are only limited periods in their lives when they show florid, overt symptoms that can be easily diagnosed. During these other times, MPD patients often show subtle dissociative signs in their affects, thoughts, memories, behaviors, object relations, and transferences. These indirect manifestations of MPD are evidence of the patient's dissociative pathology and occur when their alters influence each other, partly emerge, or subtly shift. A familiarity with these subtle dissociative signs would allow the therapist to be aware of what MPD looks like when it is camouflaged and expressed indirectly. A recognition of these indirect manifestations would enable the clinician to suspect the diagnosis, explore the possible alters, and diagnose the patient's underlying dissociative pathology when present.

Adult↗

Dissociative states and epilepsy.

Since symptoms of chronic dissociative disorders such as multiple personality disorder (MPD) may be shared by patients with seizure disorders, we investigated the possible relationship between dissociative states and epilepsy. We monitored 6 MPD patients with intensive video-EEG recordings to determine whether epileptic phenomena have any correlation to the dissociative symptoms experienced by these patients. Previously, physicians had diagnosed epilepsy in all 6 patients; however, none proved to have epilepsy. In addition, we studied dissociative symptoms in 71 epileptic patients with the aid of a standardized questionnaire, the Dissociative Experiences Scale, and compared them with age-matched controls. While the group median score of cases with complex partial seizures was higher than that of normal controls, it was significantly lower than that of the psychiatric patients with MPD. Partial seizure patients with dominant hemisphere foci had higher depersonalization subscale scores than those with nondominant foci. Our data suggest that epilepsy is not a primary pathophysiologic mechanism for developing dissociative symptoms.

Adult↗

Psychotherapy of the survivor of incest with a dissociative disorder.

The treatment of the survivor of incest who suffers from a dissociative disorder is probably somewhat more difficult than that of other survivors of incest because for these others the material is more readily available. Also the patient with DD was probably more severely abused or the dissociative defense would not have been needed. This too makes therapy difficult, especially in that most necessary step: the development of trust and rapport. Despite these problems, there is a very good chance for a successful therapy that will bring the dissociated material back into the main stream of consciousness with a "here and now" appropriate perspective. This can be accomplished through proper diagnosis, good theoretics grounding, and therapy including psychotherapy with appropriate limit setting and the judicious use of medication. This article presents a summary of the BASK model of dissociation and two other models and gives ideas on how these models may be applied to the understanding of the etiology of dissociative disorders and their treatment. Case examples are used to illustrate successful treatment. Although treatment of incest survivors with dissociative disorders is difficult, success can be anticipated, and the rewards to the patient and the satisfaction for the therapist are great.

Adolescent↗

Alexithymia and dissociative tendencies.

This study is one of a series exploring the potential of affective variables as predictors of dissociative tendencies. Some clinicians have observed that traumatized children who develop a dissociative coping style also tend to fail to discriminate emotions by verbal means. The study therefore investigated a relationship between dissociation and alexithymia. Undergraduate psychology students were individually tested for dissociative tendencies, alexithymic characteristics, and ability to generate the names of emotions. Dissociation was found to be predicted by some aspects of alexithymia but not by affective fluency. The data are interpreted in terms of the concept of asymmetry of dissociative processes.

Adolescent↗

The relationship between dissociative tendencies and schizotypy: an artifact of childhood trauma?

Previous research has suggested a relationship between dissociative tendencies and schizotypy. This study sought to extend the previous work in two fundamental respects. First, explicit cognizance was taken of the multidimensionality of both dissociative tendencies and schizotypy. Second, the study examined the possibility that the observed correlation between dissociative tendencies and schizotypy is an artifact of the association between each of these personality domains and a history of childhood trauma. Australian adults (N = 116) were administered the Dissociative Experiences Scale, the Schizotypal Personality Questionnaire-Brief, and the Childhood Trauma Questionnaire. Hierarchical regression analysis revealed that both pathological and nonpathological dissociative tendencies were predicted by the dimensions of schizotypy, even after the contribution of childhood trauma had been removed. It is concluded that the relationship between dissociative tendencies and schizotypy is not an artifact of childhood abuse, but the clinical significance of this relationship remains to be established.

Adolescent↗

The responses of dissociative patients on the thematic apperception test.

This study compared the responses of dissociative inpatients and general inpatient psychiatric controls on the Thematic Apperception Test (TAT; Murray, 1943). We found the stories of dissociative participants to be characterized by a greater interpersonal distance and more trauma and dissociation responses than those of the controls. No significant differences were found regarding total number of emotional references, although references to positive emotions were almost nonexistent for the dissociative group. A post hoc analysis of the data found the testing behaviors of dissociative participants to be characterized by switching, trance states, intrainterview amnesias, and affectively loaded card rejections. Questions were raised regarding the relevancy of the findings to clinical practice and how they might explain some of the controversies surrounding the diagnosis of dissociative identity disorder (DID).

Adult↗

Correlates of dissociative symptoms among women with eating disorders.

We examined the relationship between dissociative symptoms and other Axis I and Axis II symptoms among a sample of 53 women diagnosed as having anorexia nervosa (n = 18), bulimia nervosa (n = 27), or eating disorder NOS (n = 8). Dissociative symptoms were measured by the Dissociative Experiences Scale and the dissociation scale from the Trauma Symptom Checklist 40. Severity of dissociative symptoms was generally unrelated to severity of bulimic or anorexic symptomatology but was significantly associated with severity of anxiety and depression. In terms of Axis II symptoms, dissociative symptoms were most highly correlated with schizotypal symptomatology (r = .59), uncorrelated with borderline or antisocial symptomatology, and slightly negatively correlated with histrionic symptomatology.

Adolescent↗

Relationship between child abuse history, trauma, and dissociation in Russian college students.

OBJECTIVE: The research was conducted to determine the relationship between violent trauma, child abuse history, and dissociative symptoms in a Russian population. METHOD: Three hundred and one undergraduate students from Moscow State Linguistics University participated in the study and completed the Dissociation Continuum Scale, the Violence History Questionnaire, the Traumatic Events Survey (TES), and a demographic measure. RESULTS: Scores on dissociation and its subfactors were significantly higher in the Russian sample compared to the normative US group. The best predictors for dissociation were experiencing a violent trauma, child abuse history, and/or the experience of a fearful event. Those participants with a prior child abuse history were more symptomatic after adult trauma than those with no such history. CONCLUSIONS: The relationship between trauma/abuse and dissociation is unlikely to be a result of suggestion by therapists or media exposure, since the correlation appears in a Russian population who are relatively unexposed to these suggestive sources. The validity, reliability, and structure of the dissociation measure were relatively similar in American and Russian samples.

Adolescent↗

Dissociation and fantasy proneness in psychiatric patients: a preliminary study.

Nonclinical studies found that dissociative experiences are intimately linked to a trait known as fantasy proneness. We examined the links among dissociative symptoms, fantasy proneness, and impulsivity in psychiatric outpatients. Our sample consisted of 22 patients with schizophrenia, 20 patients with a diagnosis of borderline personality disorder, and 19 patients with a major depressive disorder. For the whole sample, levels of dissociation were found to be related to fantasy proneness and impulsivity. There were group differences in dissociative symptoms, with patients with borderline personality disorder reporting more such symptoms than patients with either schizophrenia or major depressive disorder. The overlap between dissociation and fantasy proneness may have important ramifications for studies addressing comorbid phenomena of dissociative symptoms.

Adult↗

Somatization, dissociation and general psychopathology in patients with psychogenic non-epileptic seizures.

The etiology of psychogenic non-epileptic seizures (PNES) remains uncertain. Previous studies have shown that PNES patients are characterized by high levels of somatization, dissociation and general psychopathology but a correlation of measures of these features and PNES severity or outcome has never been demonstrated, although this would strengthen a possible etiological link. This study measured somatization (Screening Test for Somatoform Symptoms-2), dissociation (Dissociative Experience Scale, DES), and general psychopathology (Symptom Checklist-90-Revised, SCL-90) in 98 patients with PNES and 63 patients with epilepsy. All mean scores were raised in the PNES compared to the epilepsy group. However, only measures of somatization and general psychopathology discriminated between patients with PNES and epilepsy in a logistic regression model (even when patient gender was controlled for). In PNES patients, high somatization scores correlated with poor outcome and greater seizure severity even after correction was made for dissociation and psychopathology. Dissociation and psychopathology scores were not independently associated with outcome or severity. The results suggest that, as a group, patients with PNES are best characterized by their tendency to express psychosocial distress by producing unexplained somatic symptoms which are brought to medical attention. Although dissociation may be relevant in some individuals it does not appear to be an independent factor across the whole PNES patient group.

Adult↗

Spontaneous dissociation during functional MRI experiments.

It is assumed that the procedures of functional magnetic resonance imaging (fMRI) are able to provoke significant dissociative responses. Trait and state dissociation of 32 healthy subjects undergoing fMRI have been recorded. At least one-third of the subjects showed dissociative responses of very large effect size (d=4.10). The contributing causal factors for that dissociative response could not yet identified clearly. Considering the impact of dissociation on mental functions, we recommend controlling subjects undergoing fMRI studies for dissociative responses. Further studies on the actual phenomenological experience of subjects undergoing fMRI procedures are warranted.

Adult↗

A preliminary study of cortisol and norepinephrine reactivity to psychosocial stress in borderline personality disorder with high and low dissociation.

The goal of the current study was to investigate subjective and neurohormonal reactivity to acute psychosocial stress in borderline personality disorder (BPD) as a function of dissociative symptoms. Five BPD subjects with high dissociation, 8 BPD subjects with low dissociation, and 11 healthy control subjects were compared in basal urinary cortisol and norepinephrine, as well as in plasma cortisol and norepinephrine reactivity to the Trier Social Stress Test (TSST). Subjective stress rating and emotional response to the TSST were also measured. The three groups differed significantly in cortisol stress reactivity, with the high-dissociation BPD group demonstrating the most robust response. The three groups did not significantly differ in norepinephrine stress reactivity. In the combined BPD sample, dissociation severity tended to be inversely correlated with basal urinary norepinephrine, was positively correlated with norepinephrine stress reactivity. Childhood trauma was inversely correlated with basal urinary cortisol. In conclusion, despite its small sample size this pilot study suggests that dissociative symptomatology may be a marker of heightened biological vulnerability to stress in BPD, and merits further study.

Acute Disease↗

Hyperarousal and dissociation: a study of novice skydivers.

Peritraumatic dissociation describes alterations in awareness that occur during or immediately after a trauma. This study investigated a simulated form of peritraumatic dissociation by indexing the responses of skydivers (N=100) who were participating in their first skydive. Prior to jumping, participants completed the Beck anxiety inventory, the Tellegen absorption scale, and ratings of predictability and uncontrollability. Immediately after the jump, they completed the peritraumatic dissociative experiences questionnaire and the physical reactions scale. Responses indicated that the skydive elicited extreme anxiety, hyperarousal, and peritraumatic dissociation in a significant proportion of skydivers. Multiple regression analyses indicated that hyperarousal, and to a lesser extent anxiety, were strongly predictive of peritraumatic dissociative reactions. These results are discussed in terms of proposals that peritraumatic dissociation is mediated by hyperarousal.

Adolescent↗

Peritraumatic dissociation and posttraumatic stress after pregnancy loss: a prospective study.

This study examined (1). predictors for peritraumatic dissociation, (2). its relations with acute and chronic symptoms of posttraumatic stress disorder (PTSD), and (3). pathways regarding these relations in response to pregnancy loss. In early pregnancy, about 1370 women volunteers completed questionnaires for neuroticism, control over emotions, dissociative tendencies, absorption, and prior life events. Of these, 126 subsequently experienced pregnancy loss and most of them completed measures 1 month (N = 118) and 4 months (N = 104) later. At 1 month, peritraumatic dissociation, memory of pregnancy loss (degree of fragmentation, sensory impressions, and emotional intensity), thought suppression, and PTSD symptoms were assessed, and at 4 months, PTSD symptoms were re-assessed. Peritraumatic dissociation was predicted by prior low control over emotions, dissociative tendencies, and lower education. It was not predicted by neuroticism, absorption, and prior life events. Peritraumatic dissociation was related to acute PTSD symptoms and LISREL analyses indicated that self-reported memory fragmentation and thought suppression of pregnancy loss mediated this relation. It also predicted chronic PTSD symptoms, and this relation was mediated by acute PTSD symptoms.

Abortion, Spontaneous↗

Dissociative experiences are related to commissions in emotional memory.

Two rival hypotheses of the link between dissociative experiences and emotional memory were tested: 1) the defence mechanism hypothesis that assumes that dissociation promotes fragmentation of emotional memory; and 2) the fantasy proneness hypothesis that claims that because of its overlap with fantasy proneness, dissociation is related to commissions in emotional memory. Undergraduates scoring high (n = 19) or low (n = 19) on the Dissociative Experiences Scale (DES) listened to an aversive story. Next, a free recall task was administered. While high dissociators made more commission errors in their free recall than did low dissociators, fantasy proneness did not account for this difference.

Adolescent↗