Modification of electrofusion by proteins Xiao, Min; Velizarov, Svetlozar; Glück, Brigitte ...
Bioelectrochemistry and Bioenergetics,
12/1996, Letnik:
41, Številka:
2
Journal Article
Extending our systematic study of “biopolymer supported electrofusion” of plant protoplasts and animal cells by 3 polypeptides and 18 proteins at concentrations in the μg ml
−1 range, not only ...enhancement of relative electrofusion yield (
F
r > 1) has been found but also inhibition (
F
r < 1). The reason for this behaviour could be explained mainly by the influence of isoelectric points (
pI) of the substances studied in the following way:
F
r > 1 at
pI > 7 corresponding to an increase of relative membrane resealing time (τ
p/τ
c > 1) and vice versa at
pI < 7, F
r < 1 and τ
p/τ
c < 1. These relationships for membranes tested have been found to be independent of molecular masses and protein adsorption behaviour on a weakly charged dropping mercury electrode. The explanation of “biopolymer modified electroporation and electrofusion” is still at an early stage. Nevertheless, addition of biopolymers at very low concentrations to the cell suspension can be used for regulation of both electroporation and electrofusion efficiencies in practical applications.
Results on the interaction between anaesthetics and human cell membranes are presented in order to show their target behavior including changes in electropermeabilization and resealing. Using ...electroporation and electrofusion techniques, it is possible to characterize the effects of anaesthetic agents which act as modifiers of cell membrane permeability depending on their types, concentrations and contact times. The field-induced uptake of trypan blue, used as a reporter of membrane electropermeabilization, and electrofusion of human lymphoma cells U 937 and human breast cancer cells MCF 7 were investigated. The cell electropermeabilization decreased with increasing external medium conductivity and osmolarity. The resealing kinetics of both types of cells studied could be fitted by exponentially decaying curves, however the first order rate constant for lymphoma cells was about two orders of magnitude higher. Moreover, the resealing step was slowed down in the presence of anaesthetics. It is suggested that the impact of anaesthetics on cell membranes may be explained by the combined action of different interaction mechanisms, electrical and/or mechanical in nature, as well as by specific bindings to integral membrane molecules, depending on the anaesthetic agent applied. It is concluded that the influence of anaesthetics on in vitro cell electropermeabilization might be used as an additional indicator for clinical purposes.
The influence of propofol (CAS 2078-54-8 (intravenous propofol emulsion) on cell membrane properties was investigated in vitro with techniques of cell electrofusion and cell electroporation. Human ...lymphoma cells and plant protoplasts were chosen as a model system. Propofol (intravenous propofol emulsion) decreased the electrofusion yield of the cells and their membrane permeability. A 50% decrease in relative electrofusion was observed in human lymphoma cells in the presence of about 0.05 mmol/l propofol (intravenous propofol emulsion) and in plant protoplasts in the presence of about 0.1 mmol/l. The fusion of human lymphoma cells was inhibited to 100% at concentrations higher than 0.2 mmol/l propofol and 0.4 mmol/l intravenous propofol emulsion. The membrane permeability of human lymphoma cells decreased by the factor of two with increasing propofol concentrations up to about 0.1 mmol/l. The effects of electroporation were highly reversible. Propofol (intravenous propofol emulsion) was more effective than tetracaine. These sensitive techniques are suitable for the investigation of interactions between anesthetic drugs and the cell membrane.
Child maltreatment (CM) in foster care settings (i.e., institutional abuse, IA) is known to have negative effects on adult survivor’s mental health. This study examines and compares the extent of CM ...(physical, emotional, and sexual abuse; physical and emotional neglect) and lifetime traumatization with regard to current adult mental health in a group of survivors of IA and a comparison group from the community. Participants in the foster care group (n = 220) were adult survivors of IA in Viennese foster care institutions, the comparison group (n = 234) consisted of persons from the Viennese population. The comparison group included persons who were exposed to CM within their families. Participants completed the Childhood Trauma Questionnaire, the Life Events Checklist for DSM-5, the PTSD Checklist for DSM-5, the International Trauma Questionnaire for ICD-11, and the Brief Symptom Inventory-18 and completed a structured clinical interview. Participants in the foster care group showed higher scores in all types of CM than the comparison group and 57.7% reported exposure to all types of CM. The foster care group had significantly higher prevalence rates in almost all mental disorders including personality disorders and suffered from higher symptom distress in all dimensional measures of psychopathology including depression, anxiety, somatization, dissociation, and the symptom dimensions of PTSD. In both groups, adult life events and some but not all forms of CM predicted PTSD and adult life events partly mediated the association of PTSD and CM. Explanations for the severe consequences of CM and IA are discussed.
Background: Anger and shame are aspects that are specifically associated with psychopathology and maladaptation after childhood abuse and neglect. They are known to influence symptom maintenance and ...exacerbation; however, their interaction is not fully understood.
Objective: To explore with network analysis the association and interaction of prolonged, complex interpersonal childhood abuse and neglect in institutional foster care settings institutional abuse (IA) with anger, shame, and the proposed 11th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-11) post-traumatic stress disorder (PTSD) symptoms in adult survivors.
Method: Adult survivors of IA (N = 220, mean age = 57.95 years) participated in the study and were interviewed using the Childhood Trauma Questionnaire, the International Trauma Questionnaire, the State-Trait Anger Expression Inventory, the Displaced Aggression Questionnaire, and shame-related items. To identify the most central aspects, we used a staged network analysis and centrality analysis approach: (1) on the scale level; (2) on the item/symptom level; and (3) with modularity analysis to find communities within the item-level network.
Results: Trait anger, anger rumination, emotional abuse, and PTSD re-experiencing symptoms played the most important roles on a scale level and were then further analyzed on the item/symptom level. The most central symptom on the item level was anger rumination related to meaningful past events. The modularity analysis supported discriminant validity of the included scales.
Conclusions: Anger is an important factor in the psychopathological processes following childhood abuse. Anger rumination is closely related to PTSD symptoms; however, anger is not a part of the proposed ICD-11 PTSD in the present study.
The proposal for ICD-11 postulates major changes for posttraumatic stress disorder (PTSD) diagnosis, which needs investigation in different samples.
To investigate differences of PTSD prevalence and ...diagnostic agreement between ICD-10 and ICD-11, factor structure of proposed ICD-11 PTSD, and diagnostic value of PTSD symptom severity classes.
Confirmatory factor analysis and latent profile analysis were used on data of elderly survivors of childhood trauma (>60 years, N=399).
PTSD rates differed significantly between ICD-10 (15.0%) and ICD-11 (10.3%, z=2.02, p=0.04). Unlike previous research, a one-factor solution of ICD-11 PTSD had the best fit in this sample. High symptom profiles were associated with PTSD in ICD-11.
ICD-11 concentrates on PTSD's core symptoms and furthers clinical utility. Questions remain regarding the tendency of ICD-11 to diagnose mainly cases with severe symptoms and the influence of trauma type and participant age on the factor structure.
A considerable amount of research has been conducted on the aversive impact of prolonged interpersonal childhood trauma, but data on possible associations with motivational concepts (self-efficacy, ...self-esteem and locus of control) in adult survivors is scarce. The purpose of this study is to investigate specific coherences between childhood abuse and adult life events with (a) motivational concepts (MC), (b) the emotion regulation strategy “goal-directed behavior” and (c) the possible mediation of emotion regulation (ER) on motivational concepts. We use data from a cross-sectional survey in Vienna (VIA-S) obtained from 220 adult survivors of prolonged interpersonal childhood trauma. In addition, we assess the Childhood Trauma Questionnaire, the Life Events Checklist for DSM-5, the subscale “Goals” (Difficulties in Emotion Regulation Questionnaire), the Short Scale for Measuring General Self-Efficacy Beliefs, the Multidimensional Self-Esteem Scale, and an extended version of the Internal-External Control Beliefs-4 Scale. An estimated multi-group path-model, divided by gender, was also conducted with the measures indicated above. Our results show that prolonged interpersonal childhood trauma directly relates to reduced self-efficacy, self-esteem, and difficulties in ER. Concurrently, ER serves as a mediator for all MC. No gender differences were observed. Associations with adult life events were only found regarding self-efficacy. This study supports the notion that prolonged interpersonal childhood trauma in institutional settings impacts ER, which further mediates MC. Despite several study limitations (e.g. lack of a control group) the presented findings underline the importance of broadening the perception of trauma sequelae as well as integrating inhibited ER strategies and MC.
Abstract The aim of this study was to explore the nature and dimensions of institutional child abuse (IA) by the Austrian Catholic Church and to investigate the current mental health of adult ...survivors. Data were collected in two steps. First, documents of 448 adult survivors of IA ( M = 55.1 years, 75.7% men) who had disclosed their abuse history to a victim protection commission were collected. Different types of abuse, perpetrator characteristics, and family related risk factors were investigated. Second, a sample of 185 adult survivors completed the Posttraumatic Stress Disorder Checklist (PCL-C) and the Brief Symptom Inventory (BSI). Participants reported an enormous diversity of acts of violent physical, sexual, and emotional abuse that had occurred in their childhood. The majority of adult survivors (83.3%) experienced emotional abuse. Rates of sexual (68.8%) and physical abuse (68.3%) were almost equally high. The prevalence of PTSD was 48.6% and 84.9% showed clinically relevant symptoms in at least one 1 of 10 symptom dimensions (9 BSI subscales and PTSD). No specific pre-IA influence was found to influence the development of PTSD in later life (e.g. poverty, domestic violence). However, survivors with PTSD reported a significantly higher total number of family related risk factors ( d = 0.33). We conclude that childhood IA includes a wide spectrum of violent acts, and has a massive negative impact on the current mental health of adult survivors. We address the long-term effects of these traumatic experiences in addition to trauma re-activation in adulthood as both bear great challenges for professionals working with survivors.
In recent years, reports of institutional abuse within the Catholic Church have emerged and research on the consequences on mental health is in its beginnings. In this study, we report findings on ...current mental health and resilience in a sample of adult survivors of institutional abuse (N = 185). We compared 3 groups of survivors that differed regarding their current mental health to investigate aspects of resilience, coping, and disclosure. The majority of the sample was male (76.2%), the mean age was 56.28 (SD = 9.46) years, and more than 50.0% of the sample was cohabiting/married. Most of the survivors reported severe mental health problems. Known protective factors (education, social support, age) were not associated with mental health in our sample. Our findings corroborate that institutional abuse has long‐term effects on mental health. We found that fewer emotional reactions during disclosure, task‐oriented coping, and optimism were associated with better mental health. The study was limited by a cross‐sectional design, but we conclude that the kind of institutional abuse reported is especially adverse, and thus typical protective factors for mental health do not apply. Future research should focus on intrapersonal factors and institutional dynamics to improve treatment for persons affected by institutional abuse.
Resumen
Spanish s by the Asociación Chilena de Estrés Traumático (ACET)
En los últimos años, los reportes de abuso institucional en la Iglesia Católica han emergido y la investigación de sus consecuencias en la Salud Mental se encuentra en sus comienzos. En este estudio reportamos hallazgos en la salud mental y resiliencia de una muestra de adultos sobrevivientes de abuso institucional (N = 185). Comparamos 3 grupos de sobrevivientes que diferían en su estado mental actual para investigar aspectos de resiliencia, afrontamiento y denuncia. La mayoría de la muestra fueron hombres (76.2%), con edad promedio de 56.3 años y más de 50.0% de la muestra era conviviente/casado. La mayoría de los sobrevivientes reportaron problemas mentales severos. Los factores protectores conocidos (educación, apoyo social, edad) no se asociaron a la salud mental en esta muestra. Nuestros hallazgos corroboran que el abuso institucional tiene efectos de larga duración en la salud mental. Encontramos que menores reacciones emocionales durante la denuncia, afrontamiento orientado a la tarea y optimismo se asociaron a una mejor salud mental. El estudio estuvo limitado por su diseño seccional cruzado, pero concluimos que la clase de abuso institucional aquí reportado es especialmente adverso, y por tanto, los factores protectores conocidos para salud mental no se aplican. Investigaciones futuras debieran enfocarse en los factores intrapersonales y la dinámica institucional para mejorar los tratamientos para personas afectadas de abuso institucional.
抽象
Traditional and Simplified Chinese s by AsianSTSS
標題：奧地利天主教會機構內童年受虐的成人倖存者精神健康的復原力因素。
撮要：近年不斷出現天主教會機構內虐待的報告，但精神健康結果研究尚在萌芽階段。本文報導一批機構內虐待的成人倖存者現存精神健康和復原力方面的發現(N=185)。現存精神健康情況分為三組，再對照其中復原力、應對和揭露各方面情形。樣本多為男性(76.2%)，平均56.3歲，而>50.0%為同居/已婚者。大多數人有嚴重精神問題。已知保護因素(教育水平，社交支援，年紀)未與精神健康相關。本研究發現證實機構內虐待對精神健康的深遠影響。較佳精神健康與揭露時較少情緒反應、任務導向的應對和樂觀有關係。 本研究受其橫斷面設計所限，但可總結為：機構內虐待特大傷害性，導致已知精神健康保護因素未能有效。未來研究應聚焦：自身因素和機構動態可否改進受機構內虐待人士的治療。
标题：奥地利天主教会机构内童年受虐的成人幸存者精神健康的复原力因素。
撮要：近年不断出现天主教会机构内虐待的报告，但精神健康结果研究尚在萌芽阶段。本文报导一批机构内虐待的成人幸存者现存精神健康和复原力方面的发现(N=185)。现存精神健康情况分为三组，再对照其中复原力、应对和揭露各方面情形。样本多为男性(76.2%)，平均56.3岁，而>50.0%为同居/已婚者。大多数人有严重精神问题。已知保护因素(教育水平，社交支持，年纪)未与精神健康相关。本研究发现证实机构内虐待对精神健康的深远影响。较佳精神健康与揭露时较少情绪反应、任务导向的应对和乐观有关系。 本研究受其横断面设计所限，但可总结为：机构内虐待特大伤害性，导致已知精神健康保护因素未能有效。未来研究应聚焦：自身因素和机构动态可否改进受机构内虐待人士的治疗。
PDF
