Effect of managed transition on mental health outcomes for young people at the child-adult mental health service boundary: a randomised clinical trial

BACKGROUND

Poor transition planning contributes to discontinuity of care at the child-adult mental health service boundary (SB), adversely affecting mental health outcomes in young people (YP). The aim of the study was to determine whether managed transition (MT) improves mental health outcomes of YP reaching the child/adolescent mental health service (CAMHS) boundary compared with usual care (UC).

METHODS

A two-arm cluster-randomised trial (ISRCTN83240263 and NCT03013595) with clusters allocated 1:2 between MT and UC. Recruitment took place in 40 CAMHS (eight European countries) between October 2015 and December 2016. Eligible participants were CAMHS service users who were receiving treatment or had a diagnosed mental disorder, had an IQ ⩾ 70 and were within 1 year of reaching the SB. MT was a multi-component intervention that included CAMHS training, systematic identification of YP approaching SB, a structured assessment (Transition Readiness and Appropriateness Measure) and sharing of information between CAMHS and adult mental health services. The primary outcome was HoNOSCA (Health of the Nation Outcome Scale for Children and Adolescents) score 15-months post-entry to the trial.

RESULTS

The mean difference in HoNOSCA scores between the MT and UC arms at 15 months was -1.11 points (95% confidence interval -2.07 to -0.14, p = 0.03). The cost of delivering the intervention was relatively modest (€17-€65 per service user).

CONCLUSIONS

MT led to improved mental health of YP after the SB but the magnitude of the effect was small. The intervention can be implemented at low cost and form part of planned and purposeful transitional care.

Demographic, clinical, and service-use characteristics related to the clinician's recommendation to transition from child to adult mental health services

PURPOSE

The service configuration with distinct child and adolescent mental health services (CAMHS) and adult mental health services (AMHS) may be a barrier to continuity of care. Because of a lack of transition policy, CAMHS clinicians have to decide whether and when a young person should transition to AMHS. This study describes which characteristics are associated with the clinicians' advice to continue treatment at AMHS.

METHODS

Demographic, family, clinical, treatment, and service-use characteristics of the MILESTONE cohort of 763 young people from 39 CAMHS in Europe were assessed using multi-informant and standardized assessment tools. Logistic mixed models were fitted to assess the relationship between these characteristics and clinicians' transition recommendations.

RESULTS

Young people with higher clinician-rated severity of psychopathology scores, with self- and parent-reported need for ongoing treatment, with lower everyday functional skills and without self-reported psychotic experiences were more likely to be recommended to continue treatment. Among those who had been recommended to continue treatment, young people who used psychotropic medication, who had been in CAMHS for more than a year, and for whom appropriate AMHS were available were more likely to be recommended to continue treatment at AMHS. Young people whose parents indicated a need for ongoing treatment were more likely to be recommended to stay in CAMHS.

CONCLUSION

Although the decision regarding continuity of treatment was mostly determined by a small set of clinical characteristics, the recommendation to continue treatment at AMHS was mostly affected by service-use related characteristics, such as the availability of appropriate services.

The ACCEPT-study: design of an RCT with an active treatment control condition to study the effectiveness of the Dutch version of PEERS® for adolescents with autism spectrum disorder

BACKGROUND

Social skills interventions are commonly deployed for adolescents with autism spectrum disorder (ASD). Because effective and appropriate social skills are determined by cultural factors that differ throughout the world, the effectiveness of these interventions relies on a good cultural fit. Therefore, the ACCEPT study examines the effectiveness of the Dutch Program for the Education and Enrichment of Relational Skills (PEERS®) social skills intervention.

METHODS/DESIGN

This study is a two-arm parallel group randomized controlled trial (RCT) in which adolescents are randomly assigned (after baseline assessment) to one of two group interventions (PEERS® vs. active control condition). In total, 150 adolescents are to be included, with multi-informant involvement of their parents and teachers. The ACCEPT study uses an active control condition (puberty psychoeducation group training, focussing on social-emotional development) and explores possible moderators and mediators in improving social skills. The primary outcome measure is the Contextual Assessment of Social Skills (CASS). The CASS assesses social skills performance in a face to face social interaction with an unfamiliar, typically developing peer, making this a valuable instrument to assess the social conversational skills targeted in PEERS®. In addition, to obtain a complete picture of social skills, self-, parent- and teacher-reported social skills are assessed using the Social Skills improvement System (SSiS-RS) and Social Responsiveness Scale (SRS-2). Secondary outcome measures (i.e. explorative mediators) include social knowledge, social cognition, social anxiety, social contacts and feelings of parenting competency of caregivers. Moreover, demographic and diagnostic measures are assessed as potential moderators of treatment effectiveness. Assessments of adolescents, parents, and teachers take place at baseline (week 0), intermediate (week 7), post intervention (week 14), and at follow-up (week 28).

CONCLUSION

This is the first RCT on the effectiveness of the PEERS® parent-assisted curriculum which includes an active control condition. The outcome of social skills is assessed using observational assessments and multi-informant questionnaires. Additionally, factors related to social learning are assessed at several time points, which will enable us to explore potential mediators and moderators of treatment effect.

TRAIL REGISTRATION

Dutch trail register NTR6255 (NL6117). Registered February 8th, 2017 - retrospectively registered.

Protocol for the development and validation procedure of the managing the link and strengthening transition from child to adult mental health care (MILESTONE) suite of measures

Background

Mental health disorders in the child and adolescent population are a pressing public health concern. Despite the high prevalence of psychopathology in this vulnerable population, the transition from Child and Adolescent Mental Health Services (CAMHS) to Adult Mental Health Services (AMHS) has many obstacles such as deficiencies in planning, organisational readiness and policy gaps. All these factors contribute to an inadequate and suboptimal transition process. A suite of measures is required that would allow young people to be assessed in a structured and standardised way to determine the on-going need for care and to improve communication across clinicians at CAMHS and AMHS. This will have the potential to reduce the overall health economic burden and could also improve the quality of life for patients travelling across the transition boundary. The MILESTONE (Managing the Link and Strengthening Transition from Child to Adult Mental Health Care) project aims to address the significant socioeconomic and societal challenge related to the transition process. This protocol paper describes the development of two MILESTONE transition-related measures: The Transition Readiness and Appropriateness Measure (TRAM), designed to be a decision-making aide for clinicians, and the Transition Related Outcome Measure (TROM), for examining the outcome of transition.

Methods

The TRAM and TROM have been developed and were validated following the US FDA Guidance for Patient-reported Outcome Measures which follows an incremental stepwise framework. The study gathers information from service users, parents, families and mental health care professionals who have experience working with young people undergoing the transition process from eight European countries.

Discussion

There is an urgent need for comprehensive measures that can assess transition across the CAMHS/AMHS boundary. This study protocol describes the process of development of two new transition measures: the TRAM and TROM. The TRAM has the potential to nurture better transitions as the findings can be summarised and provided to clinicians as a clinician-decision making support tool for identifying cases who need to transition and the TROM can be used to examine the outcomes of the transition process.

Trial registration

MILESTONE study registration: ISRCTN83240263 Registered 23-July-2015 - ClinicalTrials.gov NCT03013595 Registered 6 January 2017.

Managing the link and strengthening transition from child to adult mental health Care in Europe (MILESTONE): background, rationale and methodology

BACKGROUND

Transition from distinct Child and Adolescent Mental Health (CAMHS) to Adult Mental Health Services (AMHS) is beset with multitude of problems affecting continuity of care for young people with mental health needs. Transition-related discontinuity of care is a major health, socioeconomic and societal challenge globally. The overall aim of the Managing the Link and Strengthening Transition from Child to Adult Mental Health Care in Europe (MILESTONE) project (2014-19) is to improve transition from CAMHS to AMHS in diverse healthcare settings across Europe. MILESTONE focuses on current service provision in Europe, new transition-related measures, long term outcomes of young people leaving CAMHS, improving transitional care through 'managed transition', ethics of transitioning and the training of health care professionals.

METHODS

Data will be collected via systematic literature reviews, pan-European surveys, and focus groups with service providers, users and carers, and members of youth advocacy and mental health advocacy groups. A prospective cohort study will be conducted with a nested cluster randomised controlled trial in eight European Union (EU) countries (Belgium, Croatia, France, Germany, Ireland, Italy, Netherlands, UK) involving over 1000 CAMHS users, their carers, and clinicians.

DISCUSSION

Improving transitional care can facilitate not only recovery but also mental health promotion and mental illness prevention for young people. MILESTONE will provide evidence of the organisational structures and processes influencing transition at the service interface across differing healthcare models in Europe and longitudinal outcomes for young people leaving CAMHS, solutions for improving transitional care in a cost-effective manner, training modules for clinicians, and commissioning and policy guidelines for service providers and policy makers.

TRIAL REGISTRATION

"MILESTONE study" registration: ISRCTN ISRCTN83240263 Registered 23 July 2015; ClinicalTrials.gov NCT03013595 Registered 6 January 2017.

[Transitional psychiatry in the Netherlands: experiences and views of mental health professionals]

Psychopathology manifests itself primarily in late adolescence and continues into adulthood. Continuity of care is essential during this phase of life. The current care service distinguishes between child/adolescent (CAMHS) and adult mental health services (AMHS). The separation of services can interfere with the continuity of care.<br/> AIM: To map professionals' experiences of and views on the transition and associated problems that young people can experience as they are transferred from CAMHS to AMHS.<br/> METHOD: We distributed an online questionnaire among professionals providing mental health care to young people (aged 15-25) with psychiatric problems.<br/> RESULTS: The questionnaire was completed by 518 professionals. Decisions relating to transition were generally based on the professional's own deliberations. The preparation consisted mainly of discussing changes with the adolescent and his or her parents. The majority of transition-related problems were experienced in CAMHS, particularly with regard to collaboration with AMHS. Respondents were of the opinion that the developmental age ought to be the determining factor in the decision-making process with regard to transition and they considered it important that developmentally appropriate services should be available in order to bridge the gap.<br/> CONCLUSION: Professionals in CAMHS and AMHS are encountering problems in preparing the transitional phase and in organising the required structural collaboration between the two separate services. The problems relate mainly to coordination, communication and rules and regulations. Professionals are keen to improve the situation and want to see greater flexibility. In their view, there should be a wider range of specialised facilities for young people, enabling them to benefit from transitional psychiatry.

Developmental links between disobedient behavior and social classroom relationships in boys with psychiatric disorders in special education

In mainstream education, positive relationships with teachers and peers have been found to positively influence children's behavioral development. However, high levels of classroom behavior problems may hinder the formation of such positive relationships. Therefore, findings from mainstream education cannot be generalized to special education. The present study investigated the developmental links between disobedience and positive as well as negative relationships with teachers and peers among boys in restrictive special educational settings. At three assessment waves across one school year, teacher-reports of teacher-child closeness and conflict, and peer-reports of peer acceptance, rejection and disobedience were collected among 340 boys (mean age = 10.1 years, SD = 1.58, range = 5-13) with psychiatric disorders receiving special education. Autoregressive cross-lagged models were fitted to explore the nature of these developmental links. The impact of boys' age was examined using multiple group analyses. Findings supported the importance of teacher-child conflict, but not closeness, and positive and negative peer relationships for the development of boys' disobedience, with a stronger effect of negative than positive relationships. However, teacher-child and peer relationships were not longitudinally related and the effect of boys' age was minimal. This study extends prior research by suggesting that, despite differences in educational setting and severity of behavior problems between children in mainstream and special education, reducing negative classroom interactional patterns is most important in preventing the development of problematic classroom behavior in boys with severe social-emotional and behavioral difficulties.

Increased brain membrane fluidity in schizophrenia

Recent findings showing significant correlations between phospholipase A2 (PLA2) activity and structural changes in schizophrenic brains contribute to the membrane hypothesis of schizophrenia, which was hampered because a clean functional link between elevated PLA2 activity and brain structure was missing (Neuroimage, 2010; 52: 1314-1327). We measured membrane fluidity parameters and found that brain membranes isolated from the prefrontal cortex of schizophrenic patients showed significantly increased flexibility of fatty acid chains. Our findings support a possible link between elevated PLA2 activity in cortical areas of schizophrenic patients and subsequent alterations of the biophysical parameters of neuronal membranes leading to structural changes in these areas.

AFM for diagnosis of nanocrystallization of steels in hardening processes

INTRODUCTION

The aim of this study is to investigate the nanocrystallization of steels caused by the transformation from the austenitic to the martensitic phase induced by a severe plastic deformation (SPD) treatment. In this framework, we applied an air blast shot peening treatment, which is a simple protocol widely used for industrial purposes.

METHODS

AISI 286 and AISI 316 specimens were peened for different times and polished using diamond pastes in order to remove corrugations higher than 1 mum. The characterization of the steel surfaces was performed by atomic force microscopy (AFM) operating in contact mode. Additional EDXD measurements were performed to confirm the phase transition.

RESULTS AND DISCUSSION

An AFM-based characterization at nanometric level of the steel surfaces is provided. When the peening exceeds a threshold time that, as expected, depends on the steel composition, a uniform nanostructuration is detected. It is well known that such rearrangement is associated to the growth of a martensitic phase. To date, AFM has been employed in this field only for few applications and to solve specific problems. On the other hand, our results demonstrate that this is a useful technique for the characterization of hardened surfaces, especially when non-destructive sample preparation treatments are required. Moreover, we show that AFM can be a useful tool also for in situ industrial diagnostics of metallic parts.

Olanzapine versus flupenthixol in the treatment of inpatients with schizophrenia: a randomized double-blind trial

OBJECTIVE

The atypical antipsychotic olanzapine has extensively been compared with haloperidol, whereas studies vs. other (conventional) neuroleptics are scarce. This exploratory double-blind 4-week study was designed to compare the efficacy and the safety of olanzapine (OLA) and flupenthixol (FLU) which have recently been considered as a "partially atypical" antipsychotics.

METHODS

Twenty-eight inpatients with schizophrenia (DSM-IV) were randomly assigned for treatment with OLA (N = 15, 5-20 mg/d) or FLU (N = 13, 5-20 mg/d). The Brief Psychiatric Rating Scale (BPRS) and the Negative Symptoms Rating Scale (NSRS), plus the Patient Global Impression (PGI) and Clinical Global Impression (CGI) scales, were used to assess the efficacy of both compounds; safety was determined by using the Simpson Angus Scale (SAS) and the Abnormal Involuntary Movement Scale (AIMS) and by assessing treatment-emergent adverse events. Non-parametric statistics were applied.

RESULTS

BPRS and NSRS scores improved in both groups (exploratory tests; all p < or = 0.02). Similar results were observed for CGI-Severity, CGI- and PGI-Improvement. There were no significant group differences. Responder rates (at least 40 % decrease in BPRS total) were 9/13 OLA patients (69 %) and 9/12 FLU patients (75 %). EPS events were reported only in the FLU group (p < 0.01); FLU patients needed significantly more anticholinergic medication. Weight gain was higher in OLA patients (p < 0.01). Overall, fewer patients with adverse events were observed in the OLA group (p = 0.04). No significant changes were noted on SAS and AIMS scores.

CONCLUSION

Findings from this study suggest that overall and negative symptomatology improved in both treatment groups, while the safety and tolerability profiles differed for both substances.

Fluoxetine Versus Trimipramine in the Treatment of Depression in Geriatric Patients

INTRODUCTION

Fluoxetine, a selective serotonin reuptake inhibitor (SSRI), and trimipramine, a tricyclic antidepressant (TCA), were compared in terms of efficacy and tolerability in a six-week, parallel group, double-blind pilot study in 41 geriatric patients with major depression (61 - 85 years old).

METHOD

The Hamilton Rating Scale for Depression (HAMD-17), the Montgomery-Asberg Rating Scale (MADRS), the Adjective Mood Scale (Bf-S), the Clinical Global Impression (CGI), and the Patients Global Impression (PGI) were used to measure changes in depressive symptoms.

RESULTS

Improvement with treatment was found on all scales. Efficacy and tolerability were similar in both groups. No statistically significant differences were found.

CONCLUSION

These findings suggest that fluoxetine and trimipramine are comparable in terms of efficacy and tolerability in the treatment of major depression in geriatric patients.

Association of dopamine D4 receptor (DRD4) gene with attention-deficit/hyperactivity disorder (ADHD) in a high-risk community sample: a longitudinal study from birth to 11 years of age

BACKGROUND

In recent years, a growing number of studies has focused on the dopamine D4 receptor gene (DRD4) as mediating the susceptibility to attention-deficit/hyperactivity disorder (ADHD). While their results are contradictory, the reason for this inconsistency remains as yet unclear.

METHOD

The present study sought to examine the association between ADHD and the DRD4 exon III polymorphism during child development using longitudinal data from a high-risk community sample (n = 265, 129 females, 126 males) who have been followed from birth to 11 years of age.

RESULTS

Higher rates of ADHD were observed in boys with the 7 repeat allele of exon III than in boys with other alleles at the ages of 4 1/2 (Fisher's exact test, p = .061), 8 (p = .026), and 11 years (p = .005). Boys with this allele also exhibited higher rates of persistent disorder (p = .024). In girls, a trend towards an association (p = .055) with the 7 repeat allele emerged only at preschool age.

CONCLUSIONS

These findings provide additional evidence for the role of the dopamine D4 receptor in ADHD during the course of child development.

[Role of androgens in externalizing behavior problems in adolescents]

OBJECTIVE

While an association between androgens and different types of aggression has been well documented in male offenders, the influence of androgens on externalizing behavior in adolescents at risk for antisocial behavior has not been investigated so far.

METHODS

Plasma levels of the main androgen metabolites testosterone (T) and 5a-dihydrotestosterone (DHT) were measured in N = 119 14-year-olds (51 boys, 68 girls) from a prospective longitudinal study of children at risk. The Achenbach Child Behavior Checklist (CBCL) and the Youth Self Report Form (YSR) were used to assess externalizing behavior at age 14.

RESULTS

The CBCL revealed significant positive correlations between DHT levels and the subscales "externalizing problems" and the problem scales "aggressive behavior" and "delinquent behavior" in male adolescents. Only the YSR subscale "delinquent behavior" exhibited a marginally significant association with DHT. Neither scale showed any significant correlations between androgen levels and externalizing behavior in female adolescents.

CONCLUSIONS

Earlier findings of androgen effects on aggressive and antisocial behavior in male offenders were confirmed for male adolescents from a general population sample. The results stress the importance of the androgen metabolite DHT.

Effects of antipsychotic treatment on membrane phospholipid metabolism in schizophrenia

Several studies have shown an increased membrane phospholipid turnover in brain and blood cells of schizophrenic patients. However the specificity of these findings for schizophrenia and the effects of longterm antipsychotic treatment had yet to be demonstrated. In the present study we measured the concentrations of phospholipids in platelet membranes from 67 neuroleptic-free schizophrenic patients compared to both healthy and psychiatric controls, followed by repeated measurements during a 6 months antipsychotic treatment period. At baseline, levels of the main phospholipid components phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were decreased and lysophosphatidylcholine (LPC), a major breakdown product of phospholipid metabolism, was increased in schizophrenic patients compared to healthy and to psychiatric controls, suggesting a specificity of the findings for schizophrenia. During the first 3-weeks on antipsychotic drug treatment LPC levels decreased to control values, but increased again during the following 6 months, reaching significantly higher levels than controls at the end of this period. Thus, at least in peripheral cells an increased breakdown of phospholipids in schizophrenia appears to be present during the acute episode, being influenced only by initial antipsychotic treatment, but without evidence of a long lasting treatment effect on membrane metabolism.

[Antipsychotics and phospholipid metabolism in schizophrenia]

To date numerous in-vivo (31)P-MRS and in-vitro studies in schizophrenic patients have been able to demonstrate changes in their membrane phospholipid metabolism, which might be relevant for the cause and the therapeutic responsiveness of this disorder. Thus far, however, only limited studies exist regarding the specificity of these findings for schizophrenia and the effect of antipsychotic medication. The present study examined the composition of membrane phospholipids in platelets of 67 neuroleptic-free schizophrenic patients compared to healthy and psychiatric controls. In a subsample of the schizophrenic patients we determined the effect of antipsychotic treatment on the phospholipid metabolism during six-months follow up. While untreated patients showed a decrease in major membrane phospholipid components, i.e. phosphatidylcholine and phosphatidylethanolamine, when compared to control subjects, as well as an increase in their breakdown-product lysophosphatidylcholine (LPC), there was a significant reduction in LPC during three weeks of pharmacotherapy with haloperidol. After six months treatment with different antipsychotics some divergent effects on phospholipid metabolism in schizophrenic patients could be demonstrated. While in the long-term course LPC remained decreased under continuous therapy with typical neuroleptics, patients being treated with the atypical drug zotepine showed an increase in LPC compared to their baseline level before therapy. Thus, specific mechanisms of the different antipsychotic therapies on phospholipid metabolism might serve to explain the divergent findings of (31)P-MRS in medicated patients.

Increased platelet aggregability in major depression?

There is compelling evidence that depression constitutes an independent risk factor for cardiovascular morbidity and mortality. As exaggerated platelet reactivity is associated with an increased risk of intra-arterial thrombus formation, we studied platelet aggregability in patients with major depression both before and after 5 weeks of anti-depressant therapy as well as in healthy control subjects. Twenty-two depressed patients and 24 healthy control subjects participated in the study. Washed and rediluted platelets were stimulated with the agonists collagen and thrombin in three concentration steps. Depression was associated with a higher aggregability after stimulation with thrombin in the intermediate concentration and with collagen at the low concentration, with ceiling effects for the other concentrations. After 5 weeks of anti-depressant therapy, aggregability was somewhat less exaggerated, although this effect did not reach statistical significance. We thus conclude that major depression is associated with increased platelet aggregability, which seems to persist even under a marked improvement in depressive symptomatology. This effect may contribute to the increased cardiovascular morbidity in depressed patients.

Differential effects of trimipramine and fluoxetine on sleep in geriatric depression

The effects of trimipramine, a tricyclic antidepressant (TCA) with atypical pharmacological properties, and fluoxetine, a selective serotonine reuptake inhibitor (SSRI), were compared in an exploratory analysis using mood and polysomnographic parameters during a six-week double-blind trial in 19 depressed geriatric patients. In sleep EEG measures, trimipramine demonstrated clear-cut effects on sleep measures resulting in higher values for sleep efficiency, total sleep time, stage 2 sleep, and shorter wake time. Under fluoxetine treatment, the proportion of REM sleep was decreased and REM latency was lengthened, whereas no change in REM sleep parameters was observed in the trimipramine group. The present data suggest that early antidepressant effects of medication occur independently of drug-induced changes in objective measures of sleep, i.e. suppression of REM sleep.

Cholesterol modulates the membrane-disordering effects of beta-amyloid peptides in the hippocampus: specific changes in Alzheimer's disease

Cholesterol represents an important determinant of the physical state of biological membranes. In Alzheimer's disease (AD) brains, specific changes in the distribution of cholesterol and its membrane-ordering effects take place. In the present study, membrane fluidity was investigated at the level of the hydrocarbon core and of the heads of the phospholipid bilayers using two different fluorescent probes. Hippocampal membranes of AD brains showed a reduced fluidity in the hydrocarbon core region only. Fluidity was correlated with the cholesterol content in AD and control membranes. Aggregated beta-amyloid peptides (Abeta) disrupted brain membrane structure in AD patients and controls in the same fashion. However, this effect was correlated with the cholesterol content in AD membranes only. It is suggested that in AD the brain becomes specifically sensitive for the modulation by membrane-bound cholesterol of the membrane-disturbing and ultimately neurotoxic properties of Abeta.

Effects of beta-amyloid peptides on the fluidity of membranes from frontal and parietal lobes of human brain. High potencies of A beta 1-42 and A beta 1-43

beta-amyloid peptide (A beta) and several A beta-fragments decrease the fluidity of human cortex membranes in a concentration dependent fashion. The effect of A beta on membrane fluidity increases with peptide length, is most pronounced for A beta 1-43 and can be seen at concentrations as low as 100 nmol/l. While the fragment A beta 25-35 is active, scrambled peptide (A beta 35-25) when investigated under similar conditions shows no effects on membrane fluidity. The effect of A beta peptides on fluidity of the phospholipid bilayer is more pronounced in the hydrocarbon core (labeled with the fluorescence probe 1,6-diphenylhexa-1,3,5-triene) than in the region of the hydrophilic heads (labeled with the fluorescence probe 1-[4'-(trimethylamino)phenyl]-6-phenylhexa-1,3,5-triene). It is suggested that the effect of A beta on neuronal membranes is probably a major initial mechanism in a cascade of events finally leading to neurotoxicity and cell death in Alzheimer's disease.

Electrophoretic analysis of hydrolytic enzymes of Escherichia coli cells starved in seawater and drinking water: comparison of gelatinolytic, caseinolytic, phosphohydrolytic and hyaluronolytic activities

Starvation of four Escherichia coli clinical strains in seawater and drinking water for nine days revealed that various changes of hydrolytic enzymes were induced. Several gelatinolytic and caseinolytic activities differing in mol mass were detected both in seawater and drinking water starved cells by substrate gel electrophoresis. The major activities of gelatinase migrated with mol masses of approximately 170 kDa and approximately 45 kDa. On the contrary, hyaluronolytic activities were detected only in cells cultured in Mueller Hinton broth with average mol masses of 36 kDa and 45 kDa. Acid and alkaline phosphohydrolytic activities were detected by native electrophoresis. Both activities were decreased in number of bands in E. coli cells starved either in seawater or drinking water.

Cortical NMDA receptor properties and membrane fluidity are altered in Alzheimer's disease

NMDA receptor density as measured by the specific binding of [3H]MK 801 was significantly decreased (about 20%) in the frontal but not in the parietal cortex of postmortem brain samples of Alzheimer's disease (AD) patients (n = 21), when compared with control brains (n = 20). Membrane fluidity was not altered in the frontal cortex samples, but was slightly reduced in the parietal cortex samples of the AD patients. Since AD-specific histopathological changes (densities of senile plaques and neurofibrillary tangles) were about similar in both areas, it is concluded that the reductions of NMDA receptor densities in the frontal cortex is independent of AD-specific histopathological changes and of changes of membrane fluidity.

Decreased phospholipase A2 activity in the brain and in platelets of patients with Alzheimer's disease

Phospholipase A2 (PLA2) is a key enzyme in the metabolism of membrane phospholipids. PLA2 influences the processing and secretion of the amyloid precursor protein, which give rise to the beta-amyloid peptide, the major component of the amyloid plaque in Alzheimer's disease (AD). We investigated the PLA2 activity in two samples: in post-mortem brains from 23 patients with AD and 20 non-demented elderly controls, and platelets from 16 patients with a diagnosis of probable AD, 13 healthy controls and 14 elderly patients with a major depression. In AD brains PLA2 activity was significantly decreased in the parietal, and to a lesser degree in the frontal, cortex. Lower PLA2 activity correlated significantly with an earlier onset of the disease, an earlier age at death and higher counts of neurofibrillary tangles and senile plaques. In platelets PLA2 activity was also significantly reduced in the AD group as compared with healthy and depressed controls. The reduction of the enzyme activity in platelets correlated with an early disease onset and with the severity of cognitive impairment, indicating a relationship between abnormally low PLA2 activity and a more severe form of the illness. The present results provide new evidence for a disordered phospholipid metabolism in AD brains and suggest that reduced PLA2 activity may contribute to the production of amyloidogenic peptides in the disease. Further studies are needed to examine whether PLA2 activity in platelets may be useful as a peripheral marker for a subgroup of patients with AD.

[Relevance of metabolism of membrane phospholipids for Alzheimer dementia]

We found a decreased activity of the enzyme phospholipase A2 (PLA2) in brain tissue from 23 patients with Alzheimer's disease (AD) compared to 20 non-demented controls. The decrement was more pronounced in patients with an early onset of disease and correlated significantly with higher counts of senile plaques and neurofibrillary tangles. Decreased PLA2 activity may inhibit the secretion of the amyloid precursor protein (APP) and thus contribute to the formation of the beta-amyloid peptide, the major component of the amyloid plaque in AD. Because PLA2 activity is under genetic control, it is conceivable that the enzyme activity in the brain is related to the activity in blood cells. To test this assumption we investigated PLA2 in platelet membranes from AD patients compared to healthy and psychiatric controls. Platelets are interesting peripheral models in AD research, because they contain and secrete APP. We determined the platelet PLA2 activity in 16 patients with a "probable" AD (NINCDS-ADRDA criteria) as compared to 13 healthy controls and to 14 psychiatric patients with a major depression. There were no significant differences between the three groups regarding age and sex distribution. In the AD patients the cognitive performance was assessed with the CAMCOG and the Mini Mental State Exam (MMSE). The radioenzymatic assay for the determination of PLA2 activity is described elsewhere. Platelet PLA2 activity was significantly reduced in AD patients as compared to healthy (p < 0.03) and to psychiatric controls (p < 0.002). The reduction of the enzyme activity correlated with an early onset of the disease (rs = .43, p < 0.10) and with the cognitive impairment in the CAMCOG (rs = .55, p < 0.05). AD patients with a MMSE-score lower than 10 (median) showed significantly lower PLA2 activity (11.8 +/- 3.1) than patients with MMSE-score higher than 10 (16.2 +/- 4.6, p < 0.05). These findings in platelets are in line with our previous results in brain tissue. In both studies decreased PLA2 activity was related to a more severe form of AD (early onset, more cognitive impairment and higher number of plaques and tangles). Moreover, reduced platelet PLA2 activity was specific for AD as compared to age-matched psychiatric controls. Further studies should clarify whether PLA2 activity in platelets could be useful as a peripheral marker for a subgroup of AD.

Increased platelet phospholipase A2 activity in schizophrenia

The intracellular enzyme phospholipase A2 (PLA2) plays an essential role in the breakdown of membrane phospholipids, which regulate the physicochemical properties of the cell membrane. In the brain PLA2 has been reported to influence receptor function and signal transduction. Regarding dopaminergic neurons, data from animals experiments and from binding studies suggest that PLA2 activation reduces dopaminergic neurotransmission. In the present study we investigated intracellular PLA2 in platelets from 31 DSM-III-R paranoid schizophrenic patients (15 neuroleptic-naive) compared to 31 healthy individuals and to 31 non-schizophrenic psychiatric controls, both matched to the schizophrenics by age and sex. Platelet PLA2 activity was significantly increased in schizophrenics as compared to healthy and to psychiatric controls. Neuroleptic treatment reduced significantly the enzyme activity. Our findings in platelets suggest an accelerated breakdown of membrane phospholipids in schizophrenia. An accelerated phospholipid breakdown has also been reported in the frontal cortex from schizophrenic patients. Further studies should clarify whether increased PLA2 in the brain, as observed in platelets, could contribute to a frontal dysfunction in schizophrenia.

Decreased phospholipase A2 activity in Alzheimer brains

Phospholipase A2 (PLA2) is a key-enzyme in the metabolism of membrane phospholipids. In cholinergic neurons PLA2 controls the physico-chemical properties of neuronal membranes as well as the breakdown of phosphatidylcholine to produce choline for acetylcholine synthesis. Moreover PLA2 influences the processing and secretion of the amyloid precursor protein, which gives rise to the beta-amyloid peptide, the major component of the amyloid plaque in Alzheimer's disease (AD). In the present study PLA2 activity was investigated in post-mortem brains from 23 patients with AD and 20 nondemented elderly controls. In AD brains PLA2 activity was significantly decreased in the parietal and to a lesser degree in the frontal cortex. Lower PLA2 activity correlated significantly with an earlier onset of the disease, higher counts of neurofibrillary tangles and senile plaques and an earlier age at death, indicating a relationship between abnormally low PLA2 activity and a more severe form of the illness. The present results provide new evidence for a disordered phospholipid metabolism in AD brains and suggest that reduced PLA2 activity may contribute to the cholinergic deficit and to the production of amyloidogenic peptides in the disease.

[Accelerated breakdown of membrane phospholipids in schizophrenia--implications for the hypofrontality hypothesis]

Phospholipase A2 (PLA2) is a key enzyme in the metabolism of membrane phospholipids. We and other authors (Noponen et al., 1993) reported on increased PLA2 activity in serum and plasma from schizophrenic patients as compared to healthy and psychiatric controls. This increment in PLA2 activity could be inhibited by neuroleptic therapy. The breakdown of membrane phospholipids by PLA2 produces cytotoxic products such as lysophosphatidylcholine (LPC). We found in an independent series of studies increased PLA2 activity, decreased membrane phospholipids and increased LPC concentrations in platelets from schizophrenics, suggesting an accelerated breakdown of membrane phospholipids in the disease. To clarify the effects of PLA2 in the brain we investigated the effects of intracerebral PLA2 injections on dopaminergic neurotransmission in rats using Ungerstedt's model of rotational behaviour. Circing behaviour induced by DA agonists after unilateral PLA2 injections into the substantia nigra pars compacta were recorded. One, three and five weeks after intranigral PLA2 injection apomorphine induced an ipsilateral rotation, indicating a long lasting inhibition of ipsilateral nigrostriatal dopaminergic pathway by PLA2 application. Taken together, our findings indicate that a) at least a subgroup of schizophrenic patients shows increased PLA2 activity and consequently an accelerated breakdown of platelet membrane phospholipids, and b) in animal experiments the intranigral application of PLA2 inhibited the dopaminergic activity. How could these findings be related to the biology of schizophrenia? In schizophrenia a reduced dopaminergic activity in the frontal cortex has been hypothesized. Recent spectroscopy studies reported on an accelerated breakdown of membrane phospholipids in the frontal cortex from schizophrenics.(ABSTRACT TRUNCATED AT 250 WORDS)

Contact-induced neutrophil activation by platelets in human cell suspensions and whole blood

Platelet-dependent activation of polymorphonuclear neutrophils (PMNL) was investigated with a lumi-aggregometer in heparinized whole blood and platelet-PMNL suspensions. The lumi-aggregometer allowed us to simultaneously monitor increases in impedance or light transmission as consequences of platelet aggregation and luminol-enhanced chemiluminescence (CL) as a measure of the oxidative burst in PMNL. Aggregation and platelet-PMNL contacts were also checked by light and electron microscopy. In whole blood, adenosine diphosphate (ADP) and the thromboxane A2 mimetic U 46619 induced the aggregation (increase in impedance) and the CL, which were both suppressed by EDTA, arginyl-glycyl-aspartyl-serine (RGDS) peptide, and the absence of stirring. In contrast, FMLP caused only CL that was unaffected by EDTA, RGDS peptide, and nonstirring. Similar observations were obtained with mixed suspensions containing washed platelets and PMNL at their physiologic concentrations. ADP, U 46619, and thrombin induced both aggregation (increase in light transmission) and CL, whereas FMLP caused CL but only very weak aggregation. Exogenous fibrinogen strongly enhanced the effects of ADP and U 46619. Iloprost, EDTA, RGDS peptide, red blood cell (RBC) ghosts, and nonstirring inhibited the effects induced by the platelet agonists, but were ineffective on the CL induced by FMLP. Treatment of platelets with aspirin did not affect the CL of PMNL induced by platelets. Microscopic examination, the requirements of stirring, Ca2+, and fibrinogen, and the inhibitory effects of RGDS peptide and RBC ghosts show that stimulated platelets activate PMNL in a contact-dependent manner that depends on fibrinogen binding. This was confirmed by the immunochemical demonstration of fibrinogen (but not of fibronectin) in the contact spaces between activated platelets and PMNL. Because supernatants and lysates of resting or thrombin-stimulated platelets did not induce the CL of PMNL, soluble agonists did not appear to be involved. Nonstimulated washed platelets also caused CL of PMNL that required stirring and Ca2+ and was inhibited by RBC ghosts. No CL occurred in unstimulated stirred whole blood, suggesting that a preactivation of platelets during the preparation may be responsible for the effects of unstimulated washed platelets. The results show that platelets provide a strong stimulus for PMNL that requires intercellular contact. Fibrinogen exposure on the platelet surface seems to be necessary for the activation of PMNL by stimulated platelets.