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1.
Eur Child Adolesc Psychiatry ; 33(1): 303-313, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36792866

RESUMO

Emergency inpatient admissions of children and adolescents are more difficult if the patient is admitted involuntarily and/or the caregivers or custodians of institutional care are absent. The present study aimed to clinically characterize involuntary versus voluntary admissions by examining the reasons for presentation and associated factors. We retrospectively analyzed patients who presented to the emergency department of a hospital for child and adolescent psychiatry in Bavaria, Germany, and were admitted as inpatients for crisis intervention in the 4th quarter of 2014-2018. Reasons for presentation, clinical and sociodemographic characteristics, and type of admission (voluntary versus involuntary) were analyzed for 431 emergency inpatient admissions. A total of 106 (24.6%) patients were involuntarily admitted. In a binominal logistic regression, presentation due to alcohol consumption, deviant social behavior, and psychosocial burden was positively associated, whereas difficulties at school and depression were negatively associated, with the likelihood of involuntary admission. 58.5% of the 123 unaccompanied patients were admitted involuntarily. Reasons for the presentation of unaccompanied and voluntary inpatient admissions were suicidal thoughts, psychosocial burden, and externalized aggression. A substantial number of child and adolescent psychiatric admissions represent emergency admissions. Involuntarily admitted patients and unaccompanied children/adolescents represent a non-negligible proportion of clinical routine and the clinical and legal background factors need to be further clarified in future studies. This study is registered in the German Clinical Trials Register (24 September 2019, DRKS00017689).


Assuntos
Transtornos Mentais , Admissão do Paciente , Adolescente , Criança , Humanos , Pacientes Internados , Psiquiatria do Adolescente , Estudos Retrospectivos , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Internação Compulsória de Doente Mental , Hospitais Psiquiátricos , Alemanha/epidemiologia
2.
Psychoneuroendocrinology ; 160: 106681, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38086319

RESUMO

A virtual version of the Trier Social Stress Test (TSST) has been increasingly used in stress research. Benefits of the virtual TSST include that it is more economical, and offers improved control of context and enhanced flexibility of use. Many studies have confirmed the applicability of virtual TSSTs in stress research, but only in adulthood. In the present study, we aimed to experimentally verify the transferability of a virtual TSST to adolescence. A total of 73 healthy adolescents (aged 11-17 years) of both sexes completed either a real (IV-TSST-C) or virtual (VR-TSST-C) TSST for children. The surveyed stress parameters included salivary cortisol and alpha amylase concentrations, heart rate, heart rate variability, and subjective stress ratings across test sessions, as well as a pre- to post-TSST-C comparison. All parameters revealed significant stress responses over time. We observed significant effects of group on cortisol and subjective stress ratings, with the VR-TSST-C inducing less stress than the IV-TSST-C. In alpha amylase, heart rate, and heart rate variability, we found no significant difference between TSST versions, but only significant equivalence for alpha amylase. Some parameters may have been influenced by an expectancy effect and the participant's sex. In conclusion, among adolescents, a virtual TSST-C effectively elicits stress at multiple levels (endocrinological, autonomic, and subjective); however, the magnitude is not always comparable to with the real TSST-C, which should be considered when applied.


Assuntos
Hidrocortisona , Estresse Psicológico , Masculino , Feminino , Criança , Humanos , Adolescente , Testes Psicológicos , Sistema Nervoso Autônomo , alfa-Amilases , Saliva
3.
J Eat Disord ; 11(1): 180, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828587

RESUMO

BACKGROUND: In the course of the COVID-19 pandemic, a steady increase in adolescent anorexia nervosa admissions has been observed. Contributing factors may have been uncontrollable changes in school attendance due to lockdowns and social restrictions. However, patients' reports on the impact of these factors have not been assessed in detail as of yet. Furthermore, alexithymia, the difficulty to identify and describe one's own emotions, has increased during the pandemic and is known to be heightened in eating disorders. Thus, it may have contributed to symptom severity in anorexia nervosa during the pandemic. METHODS: The present study examined pandemic-related changes in social media use, body satisfaction, and perceived loss of control and their impact on depressive, anxious, and eating disorder symptomatology in a sample of adolescent girls with anorexia nervosa (n = 29) and healthy controls (n = 23). Additionally, the influence of current alexithymia as a cross-diagnostic risk factor was assessed. Adolescents answered questionnaires once shortly after admission to inpatient, outpatient, or daycare treatment. RESULTS: An increase in perceived loss of control during the pandemic and heightened alexithymia explained a significant portion of variance in present depressive symptomatology, which in turn contributed to eating disorder symptomatology. CONCLUSIONS: These relationships emphasize alexithymia and perceived loss of control as valuable constructs for early screenings and interventions.

4.
PLoS One ; 18(2): e0281627, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36780506

RESUMO

BACKGROUND: Internalizing problems are common in young children, often persist into adulthood, and increase the likelihood for subsequent psychiatric disorders. Problematic attachment, parental mental health problems, and stress are risk factors for the development of internalizing problems. COVID-19 lockdown measures have resulted in additional parental burden and especially their impact on preschool children has rarely been investigated as of now. The current study examined the impact of sustained preschool attendance, parental stress, and parental mental health on internalizing and externalizing problems during COVID-19 lockdown measures in a sample of preschool children in Germany. METHODS AND FINDINGS: N = 128 parents of preschool children filled out a one-time online survey about children's internalizing problems, externalizing problems, and attachment for three time points: before a nation-wide lockdown (T1), during the most difficult time of the lockdown (T2) and after the lockdown (T3). Additionally, parents answered questions about their own depressive and anxious symptomatology for the three time points and parental stress for T1 and T2. Linear-mixed effect models were computed to predict children's internalizing / externalizing behavior. Preschool children showed a significant increase in internalizing and externalizing problems over time, highest at T2 with small decreases at T3. Parental depressive and anxious symptomatology increased significantly from T1 to T2, but also remained high at T3. Parental stress levels were comparable to community samples at T1, but attained average values reported for at-risk families at T2. Linear-mixed effect models identified higher parental stress, parental anxiety, attachment problems, parental education, and less preschool attendance as significant predictors for internalizing and externalizing problems in preschoolers with more specific associations shown in separate models. A limitation is the retrospective assessment for the times T1 and T2. CONCLUSIONS: Preschool children's mental health is strongly and negatively influenced by the ongoing COVID-19 pandemic and its lockdown measures. Sustained preschool attendance may serve as a protective factor.


Assuntos
COVID-19 , Saúde Mental , Humanos , Pré-Escolar , Estudos Retrospectivos , Pandemias , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Pais/psicologia
5.
Psychopathology ; 56(1-2): 148-161, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36195074

RESUMO

INTRODUCTION: The successful treatment of adolescents almost always requires parents' involvement in the treatment process. Thus, parental involvement will impact further treatment, especially concerning the acute management of self-harming behavior of their children. Parental burden or low parental motivation for treatment can significantly affect the success of the intervention. Therefore, this study aimed at investigating how especially motivational factors of the adolescents and parents, as well as stressors of the parents, affect the course of non-suicidal self-injury (NSSI) after an acute psychiatric emergency presentation. METHODS: Ninety-six adolescents aged 11-18 years who have been presented to an emergency service at a child and adolescent psychiatry clinic for suicidal and/or NSSI behavior were recruited together with their accompanying parents within the framework of a specified diagnostic procedure. This included detailed questionnaire and interview procedures for psychiatric assessment. The extent of parental stress and parents' motivation for treatment and its relations to adolescents' NSSI and own treatment motivation have been investigated in a follow-up examination in the aftermath of the acute presentation. We predicted adolescents' NSSI at follow-up based on their own motivation and parental motivation and stress. RESULTS: Data analysis demonstrated that higher adolescents' treatment motivation was associated with higher parental stress. Also, higher parental treatment motivation was correlated with a higher degree of parental distress. Furthermore, parents showed lower treatment motivation when their children engaged in NSSI for a longer duration. Finally, lower adolescents' motivation and lower parental stress due to own parental concerns were predictive for higher adolescents' NSSI frequency at follow-up investigation. DISCUSSION/CONCLUSION: Patients as well as their parents who present for an emergency service are especially likely to be exposed to increased stress and strain factors. During treatment, additional focus should be placed on parental stress and parental and adolescents' treatment motivation. Identifying and addressing deficits in motivation, increases in parental stress, as well as offering support could favorably impact future NSSI behavior.


Assuntos
Comportamento do Adolescente , Serviços de Emergência Psiquiátrica , Comportamento Autodestrutivo , Humanos , Adolescente , Criança , Motivação , Pais/psicologia , Comportamento Autodestrutivo/psicologia , Inquéritos e Questionários , Comportamento do Adolescente/psicologia
6.
BJPsych Open ; 9(1): e1, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36451604

RESUMO

Owing to restrictions of the COVID-19 pandemic, increased stress is evident in university students with a lifetime history of non-suicidal self-injury (NSSI). Therefore, we examined two groups of university students (n = 174) in an online survey, one that exhibited early NSSI in adolescence (n = 51) and another that exhibited continuous NSSI beyond the age of 18 (n = 123) (German Clinical Trials Register DRKS00023731). We compared the two groups in terms of depressive symptoms in the previous 2 weeks as well as self-perceived changes in emotional burden, urge to self-injure and NSSI frequency in the first year of the pandemic compared with the year before (pre-pandemic). Among other findings, both groups showed an increase in emotional burden and urge to self-injure.

7.
Trials ; 23(1): 847, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195934

RESUMO

BACKGROUND: Acute and everyday stress is substantial for the development of mental and physical diseases, therefore it is crucial to get a better understanding of its pathogenesis. Different methods (e.g., Ambulatory Assessment) and stress reactivity paradigms (e.g., Trier Social Stress Test / TSST) in laboratory settings are often used to investigate basic mechanisms of this process. Due to the technological progress of the last years and especially due to children and adolescents growing up with it, the application of these developments in clinical research is reasonable. The aim of this project is to successfully transfer the TSST for children and adolescents into the virtual world, which will be compared to a real TSST situation. Physiological and psychological stress reactions will be analyzed in order to assess similarities and differences. Moreover, it will be investigated whether a Heart Coherence Exercise (HCE) has a stronger influence on coping with acute stress compared to Natural Relaxation (NR). METHODS: This single-center experimental study will examine acute and everyday stress and coping processes in eighty-four healthy children and adolescents between the ages of 11 and 17. For everyday stress, different parameters (e.g., hormonal profiles and mood ratings) as well as a history of stressful life events and utilized coping methods will be recorded and a relaxation exercise will be practiced on a smartphone over 2 days. Regarding the acute stress reaction, the participants will be confronted either with the virtual or the real version of the TSST, followed by the trained relaxation exercise (HCE vs. NR). Physiological (e.g., cortisol and heart rate) and psychological stress markers (e.g., mood and gaze behavior) will be recorded continuously. DISCUSSION: Studies are sparse using a virtual version of the TSST in children and adolescents. A successful virtual TSST would constitute an economical variant, which would also make it easier to administer it in clinical or population-based samples. Effective ambulatory relaxation exercises would be a useful addition to clinical treatment approaches. TRIAL REGISTRATION: The study is registered in the German Clinical Trials Register since 10 August 2020 ( DRKS00022063 ).


Assuntos
Hidrocortisona , Aplicativos Móveis , Adolescente , Criança , Dieldrin/análogos & derivados , Humanos , Testes Psicológicos , Ensaios Clínicos Controlados Aleatórios como Assunto , Saliva , Estresse Psicológico/etiologia
8.
Neuroimage Clin ; 36: 103195, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36137498

RESUMO

BACKGROUND: Adolescence is a crucial period for both brain maturation and the emergence of mental health disorders. Associations between brain morphology and internalizing/externalizing symptomatology have been identified in clinical or at-risk samples, but age-related developmental differences were rarely considered. The current study investigated the longitudinal relationship between internalizing/externalizing symptoms and brain development in the absence of psychiatric disorders during early and late adolescence. METHODS: 98 healthy adolescents within two cohorts (younger: 9 years, older: 12 years) participated in annual assessments for three years; a clinical assessment measuring their externalizing and internalizing symptoms (SDQ) and an MRI assessment measuring their brain volume and white matter microstructure, including fractional anisotropy (FA), mean diffusivity (MD) and average path length. RESULTS: Linear mixed effect models and cross-lagged panel models showed that larger subcortical gray matter volume predicted more externalizing symptoms in older adolescents whereas decreases of subcortical gray matter volume predicted more externalizing symptoms for younger adolescents. Additionally, longer average white matter path length predicted more externalizing symptoms for older adolescents, while decreases in cerebral white matter volume were predictive of more externalizing symptoms for younger adolescents. There were no predictive effects for internalizing symptoms, FA or MD. CONCLUSIONS: Delays in subcortical brain maturation, in both early and late adolescence, are associated with increases in externalizing behavior which indicates a higher risk for psychopathology and warrants further investigations.


Assuntos
Transtornos Mentais , Substância Branca , Adolescente , Humanos , Estudos Longitudinais , Substância Branca/diagnóstico por imagem , Imageamento por Ressonância Magnética , Anisotropia
9.
Front Psychol ; 13: 901249, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992448

RESUMO

Background: In the early phase of the COVID-19 pandemic, many restrictions hit people in ways never seen before. Mental wellbeing was affected and burden was high, especially for high-risk groups such as parents. However, to our knowledge no research has yet examined whether being a parent was not only a risk for psychological burden but also a way to cope with the COVID-19 pandemic. Methods: An online survey was used to collect data from 1,121 participants from April to June 2020. In addition to demographic variables, risk factors (financial burden, problems complying with COVID-19 restrictions, and pre-treatment due to mental health problems) and protective factors (emotion regulation, humor, and crisis self-efficacy) were collected. The dataset was divided into three groups: parents whose children lived at home (n = 395), parents whose children did not (no longer) live at home (n = 165), and people who were not parents (n = 561). Results: A linear mixed effect model showed that parents had no higher burden than non-parents, and even less when children did not live at home. Expected risk factors were generally less important, and there were no differences between parents and non-parents. In contrast, parents had advantages in protective factors. Conclusion: In the early phase of the COVID-19 pandemic, it was shown that parents (with and without their children at home) were not necessarily at risk due to additional burden, but also had prospects of coping better with the situation than people without children.

10.
Front Psychiatry ; 13: 902964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873231

RESUMO

Background: The management of emergency presentations at child and adolescent psychiatric outpatient clinics, by children and adolescents with self-injurious thoughts and behaviors, represents very responsible tasks but also offers the opportunity for immediate interventions. The stability and degree of emotional reactivity (ER) is a significant psychopathological symptom for development and maintenance of self-injurious behavior, differentiating between those who have continued to injure themselves and those who have not. In general, the relationship between ER and self-injurious behavior has been shown to be bidirectional. However, the stability of ER over time, as well as important predictors for ER itself have not been investigated so far. Therefore, this present study aimed at investigating the stability of ER over time and the relationship between non-suicidal self-injury (NSSI) and ER. Reinforcement functions and several variables of psychological functioning were considered as possible influencing factors. Methods: As part of a longitudinal study, 97 adolescents aged 11-18 years who presented due to self-injurious thoughts or behaviors underwent standardized emergency management. This included a specified detailed psychiatric assessment at baseline (including the Emotion Reactivity Scale, ERS, and the Self-Injurious Thoughts and Behaviors Interview, SITBI) and treatment recommendations. These were followed by a catamnestic examination with two follow-up appointments. Changes over time in ER, NSSI, reinforcement functions of NSSI and general indicators of psychological functioning (General Severity Index, GSI) were examined and significant correlations were followed up by a linear-mixed effect model predicting the ERS score over time. Results: Data analysis revealed a statistically significant decrease in ERS scores and GSI over time. However, reinforcement functions for and the symptomatology of NSSI did not change. Furthermore, no predictive relationship from ER to NSSI could be identified. A linear-mixed effect model predicting the ERS identified the GSI, automatic positive reinforcement (as a reinforcement function for NSSI) and age as the only significant predictors. Conclusion: Results demonstrate the importance of NSSI reinforcement functions for heightened emotional reactivity and emphasize their role as a point for therapeutic intervention by providing alternatives to NSSI and thereby possibly reducing emotional reactivity.

11.
BJPsych Open ; 8(2): e57, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236539

RESUMO

BACKGROUND: Depressive disorders are common mental health problems during adolescence. Many adolescents with depression describe difficulties with sleeping. Findings of previous studies regarding changes in objective sleep quality in adolescents with depressive disorders are heterogeneous. AIMS: This study aims to investigate differences in objective and subjective sleep quality between adolescents with depressive disorders and healthy peers, and to evaluate if potential changes in sleep occur concurrently with changes in the release of cortisol and alpha-amylase after awakening. METHOD: This non-interventional parallel study examines correlations between depressive disorders, sleep quality and release of stress hormones. Sleep quality in the past 2 weeks, severity of depressive symptoms, psychiatric comorbidities and stress response of 30 adolescents with depressive disorders and 30 healthy controls (N = 60) are assessed via questionnaires. In participants' home environments, the objective sleep quality of seven consecutive nights is measured by sleep accelerometry. After awakening, participants answer sleep questionnaires to examine the subjective sleep quality of those nights. Furthermore, salivary cortisol and alpha-amylase are measured three times after awakening (+0 min, +30 min and +45 min after awakening). CONCLUSIONS: Sleep is an important factor for prognosis and well-being in adolescents with depression. The results of this study can be highly valuable to integrate a more detailed examination of sleep quality and sleeping impairments in the treatment of adolescent depressive disorders.

12.
Front Psychiatry ; 12: 708208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335339

RESUMO

Background: Children and adolescents who present to child and adolescent psychiatric emergency departments show a variety of reasons for their presentations. Suicidality, in particular suicidal thoughts and suicide attempts, as well as non-suicidal self-injury (NSSI) play a large and important role. In this context, inpatient admissions frequently serve as crisis intervention. Methods: In this study, face-to-face emergency presentations to the emergency department at our Clinic of Child and Adolescent Psychiatry (CAP) were analyzed over the years 2014-2018, the 4th quarter (October-December) of each year. Data from 902 emergency presentations were evaluated, primarily with regard to suicidal thoughts, suicide attempts, and NSSI as reasons for presentation. Results: Data demonstrated that the number of emergency presentations increased in general and especially for suicidal thoughts and NSSI as reasons for presentation. In addition, suicidal thoughts, suicide attempts, and NSSI as reasons for emergency presentation were more likely to result in crisis-related inpatient admissions. Furthermore, reporting suicide attempts at emergency presentation was associated with longer inpatient stays. Finally, cases with multiple diagnoses increased independent of the general increase in emergency presentations. Conclusion: The increase of utilization of clinics with CAP outpatient emergency patients and following admissions to the inpatient units for crisis intervention poses a major challenge for the future. It is important to prepare for the assessment and treatment of suicidality, which is of extraordinary importance in the care of emergency patients.

13.
Front Psychiatry ; 12: 634346, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177642

RESUMO

Background: Adolescents presenting in a child and adolescent psychiatric emergency service show various psychiatric disturbances, most commonly suicidal ideation, suicide attempts, and non-suicidal self-injury (NSSI). It was postulated that especially disturbed emotion regulation contributes to self-injurious behavior of young people. This study aims to investigate the relevance of emotional reactivity (ER), as part of emotion regulation, during an acute crisis, how it relates to self-injurious behavior reinforcement and how a family as well as peers' history of self-injurious behavior are associated with self-injurious behavior of presenting adolescents. Additionally, crisis-triggering background factors were evaluated from the perspective of patients and their caregivers. Methods: A consecutive sample of 86 adolescents aged 11-18 years presenting to the emergency outpatient department due to self-injurious thoughts and behavior received a pretreatment psychiatric evaluation. Among other psychometric measures and structured clinical interviews, ER was measured via the Emotion Reactivity Scale (ERS). Family-related aspects were collected both through evaluation of history and through questionnaires filled in by custodians or parents. Results: Data analysis revealed that suicidal ideation was significantly related to family history with self-injurious behavior in comparison with a family background without such a history. A significant positive correlation was apparent between the ERS sensitivity score and occurrence of NSSI within the past year. A relationship between the ERS and distinct types of reinforcement as a motivation factor for NSSI was found. Post-hoc tests revealed a significant difference between boys and girls when no positive peers' history is present with boys having lower ERS scores than girls, but no difference when both groups had friends engaging in self-injurious behavior. There was only moderate agreement between parents and their children in naming reasons for the current crisis involving NSSI. Conclusion: Emotional regulation, especially ER, has an influence on patients' acute psychiatric symptomatology and when experiencing an acute crisis should be brought into focus early at psychiatric assessment. A history of self-injurious behavior taken from patient's family members and close circle of friends and agreement on reasons for the crisis should be routinely included in the exploration of a patient presenting with self-injurious behavior.

14.
BMC Psychol ; 9(1): 61, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902711

RESUMO

BACKGROUND: In social neuroscience, the linkage between the endocrinological system and the etiology and symptomatology of mental health problems has received increasing attention. A particular focus is given to the neuropeptide oxytocin with its anxiolytic and stress-buffering effect and the resulting therapeutic potential for anxiety disorders. Even though anxiety disorders are the most prevalent mental health disorders in childhood and adolescence worldwide, the reactivity of the endogenous oxytocin system to an acute stressor (Trier Social Stress Test, TSST) has so far only been investigated in healthy children. It has been shown that peripheral oxytocin levels increased under psychosocial stress conditions. In the present study, it is hypothesized that the endogenous oxytocin system in children and adolescents suffering from a clinically diagnosed anxiety disorder is dysregulated. Three primary outcome parameters will be analyzed: significant differences between participants with anxiety disorders compared to healthy controls in basal oxytocin levels, varying salivary oxytocin release after stress exposure and the correlation between the cortisol peak/-decrease and oxytocin level over time. Secondary outcome criteria are significant differences in physiological (heart rate) and psychological (perceived stress, anxiety, insecurity, tension) responses. METHODS: The present study is a single-center experimental observation study to investigate the reactivity of the endocrinological system to a psychosocial stressor (TSST). 32 children and adolescents (11-18 years) suffering from anxiety disorder will be compared to a matched healthy control group. After a detailed psychological assessment, saliva samples will be taken to measure oxytocin levels before and after psychosocial stress exposure at eight different time points. Additionally, the stress hormone cortisol will be analyzed according to the same procedure. DISCUSSION: Due to the high prevalence and comorbidity rate with numerous other psychiatric disorders and mental health problems, there is an urgent need to strengthen research in possible neurobiological underpinnings of anxiety disorders. To our knowledge, the proposed experiment is the first study to examine the endocrinological oxytocin and cortisol reaction to an acute psychosocial stressor in children and adolescents with mental health disorders. Trial registration The study is registered in the German Clinical Trials Register since 11 September 2019, DRKS00017793, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00017793 .


Assuntos
Ocitocina , Estresse Psicológico , Adolescente , Ansiedade , Transtornos de Ansiedade , Criança , Humanos , Hidrocortisona , Ensaios Clínicos Controlados Aleatórios como Assunto , Saliva
15.
Int J Colorectal Dis ; 18(4): 292-9, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12774243

RESUMO

BACKGROUND AND AIMS: The prognostic relevance of sialyl Lewis X (sLeX) expression in colorectal and gastric cancer and its relevance to the hematogenous phase of tumor invasion is controversial. This study was designed to evaluate sLeX expression during tumor cell-endothelial cell interaction in vitro. METHODS: Adhesion and transendothelial penetration of MKN45, PaCa-2, WiDr, or Dan-G cells was analyzed by combined phase contrast-reflection interference contrast microscopy. In parallel, kinetics of membranous sLeX expression were examined fluorimetrically. To identify factor(s) which may be responsible for sLeX expression during tumor invasion tumor cells were treated with soluble immunomodulators, isolated endothelial plasma membranes, or E-selectin or P-selectin IgG fusion proteins. sLeX was then analyzed by flow cytometry. RESULTS: Fluorometric quantification of sLeX demonstrated an inverse correlation between basal sLeX expression level and adhesion capacity of the tumor cells. Unexpectedly, sLeX was strongly down-regulated on tumor cell membranes in the course of heterophilic cell-cell contacts. The process occurred transiently, with a maximum effect 30-60 min after introducing tumor cells to the endothelial monolayer. Binding of tumor cells to immobilized E- and P-selectin IgG globulin chimeras was shown to be responsible for this phenomenon. CONCLUSION: A transient loss of sLeX is necessary for gastrointestinal tumor cells to invade endothelial cells. Due to the transient nature of the decrease in sLeX the controversy about the prognostic relevance of sLeX expression in colorectal and gastric cancer may be rooted in the stage of tumor invasion at the time of sLeX measurement.


Assuntos
Adesão Celular , Selectina E/farmacologia , Neoplasias Gastrointestinais/patologia , Oligossacarídeos/biossíntese , Selectina-P/farmacologia , Regulação para Baixo , Endotélio/citologia , Citometria de Fluxo , Humanos , Imunoglobulina G/análise , Cinética , Antígenos do Grupo Sanguíneo de Lewis , Antígenos CD15 , Ligantes , Invasividade Neoplásica/fisiopatologia , Antígeno Sialil Lewis X , Células Tumorais Cultivadas
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