[Autism spectrum disorder and schizophrenia: a challenging differential diagnosis]

Autism spectrum disorder and psychotic disorders/schizophrenia are separate disorders in the DSM-5. Due to overlapping symptoms and increased frequency in comorbidity they can be a diagnostic and therapeutic challenge in clinical practice. Relevant literature regarding the correlation between these disorders is discussed and linked to a case-report. An increased prevalence of autism/autistic traits is observed within psychotic patients and vice versa. Common symptoms and risk-factors, but also differential factors, are described. Despite of several hypotheses concerning increased frequency in comorbidity, no clear explanation was found so far. Little is known concerning treatment in case of comorbidity. In this case-report there was significant amelioration after treatment with an atypical antipsychotic. Psycho-education and attention to structuring are also important elements of the treatment plan.

[The vision of interdisciplinary teams on an ambulatory nursing consultation]

BACKGROUND

Several European countries are reforming their mental healthcare program. This implies an increase of pressure on outpatient care and also in Flanders are waiting times long in the outpatient care and patients don’t receive timely care. Hitherto, a nursing consultation in mental health care is a fairly new concept of care.

AIM

To explore mental health care professionals’ point of view on outpatient nursing consultation in mental health care.

METHOD

An explorative qualitative research with semi-structured interviews was conducted. Fifteen mental health care professionals from different wards were interviewed. A thematic analysis was used.

RESULTS

Three main topics emerged: content, purpose and conditions for nursing consultation. The central topic of consultation should be patients’ quality of life when dealing with a mental illness and how support can be offered. The respondents found that the nurse functions as a mediator and provides continuity by playing an important role in observing and reporting.

CONCLUSION

The research contributes to identifying the mental healthcare professionals’ view on nursing consultation in outpatient mental health care. The implementation of nursing consultation has to meet several conditions such as the nurse’s competences and training, interprofessional collaboration and organizational concerns e.g. financing and staffing.

Family involvement in forensic psychiatric care: a professionals’ perspective

Introduction

Research shows that family members of forensic patients often have the feeling not to be sufficiently involved in the treatment and care trajectories of their relative. Also professionals indicate to encounter several barriers to involve family members, including lack of time and skills, organizational barriers and meddling family members.

Objectives

This study aimed to map professionals’ reflections on family involvement in forensic psychiatric care. The research questions related to how professionals experience family involvement in forensic care and what needs to change in the future? A specific focus is placed on changes in their perspective over time.

Methods

Findings of focus groups administered in 2015 with professionals working in forensic psychiatric care were supplemented with interview data collected in 2021.

Results

The results show that there are several differences in how professionals experience and look at family involvement in forensic psychiatric care. Where in 2015 the question often was raised about what can be done as a professional for family members, professionals now more refer to the added value of family involvement for both the forensic patient and his/her care trajectory.

Conclusions

The past six years, there seemed to be an evolution in how professionals experience the involvement of family members in forensic psychiatric care, that is increasingly perceived as valuable. Yet, the professionals indicated that challenges remain regarding professional confidentiality and shared decision making.

Disclosure

No significant relationships.

[Depression and intermittent hypercortisolism: a difficult differential diagnostic process]

Both Cushing’s and pseudo-Cushing’s syndrome involve a state of hypercortisolism. Cushing’s syndrome is a progressive multisystemic disease, caused by either the administration of corticosteroids, or the overproduction of cortisol by a tumoral process. In pseudo-Cushing’s syndrome the HPA-axis is hyperactive due to a pathophysiological process, most frequently caused by depression. The existence of a cyclic variant of Cushing’s syndrome, characterised by intermittent hypercortisolism, complicates the diagnosis in a patient with for example depression. In case of remaining intermittent hypercortisolism after remission of the depression, extreme hypercortisolism and (suspicion of) a tumor, we have to consider a cyclic Cushing syndrome. Also, in patients with treatment resistant depression or depression with atypical features combined with intermittent hypercortisolism psychiatrists have to consider a cyclic Cushing syndrome.

“Time does not heal all wounds”: mental health impact of sexual victimisation in old age

Background

Sexual violence (SV) has an important impact on mental health. Childhood sexual abuse is linked to internalizing disorders in later life. In older adults, SV occurs more often than previously believed. Moreover, health care workers lack the skills to adequately address SV in later life. Studies researching the mental health impact of lifetime SV, i.e. SV that happened during childhood, adulthood and old age, are currently lacking. In this study we research the association between lifetime sexual victimization and adverse mental health outcomes in older adults, and its moderators.

Methods

Between July 2019 and March 2020, 513 older adults living in Belgium participated in a structured face-to-face-interview. Selection occurred via a cluster random probability sampling with a random walk finding approach. Depression, anxiety and post-traumatic stress syndrome (PTSD) were measured using validated scales. Suicide attempts and self-harm were questioned during lifetime and in the past 12-months. SV was measured using behaviorally specific questions based on a broad definition of SV.

Results

Over 44% experienced lifetime SV, 8% in the past 12-months. Rates for depression, anxiety and PTSD were 27%, 26% and 6%. Almost 2% committed suicide, 1% reported self-harm in the past 12-months. Lifetime SV was linked to depression (p =.001), anxiety (p =.001), and PTSD in participants with a chronic illness/disability (p = .002) or no/lower education (p <.001). We found no link between lifetime SV and suicide attempts or self-harm in the past 12-months.

Conclusions

Lifetime SV is linked to mental health problems in late life. Tailored mental health care for older SV victims is necessary. Therefore, capacity building of professionals and development of clinical guidelines and care procedures are urgently needed.

Key messages

The mental health impact of sexual victimisation continues into old age. Tailored mental health care for older SV victims and capacity building of professionals are of the utmost importance.

Prevalence and nature of sexual violence in a gerontopsychiatric population in flanders

Introduction

Sexual violence (SV) is an important public health concern which may induce important and long lasting mental health problems. However, studies on SV and its mental health impact on older adults and more specifically gerontopsychiatric patients are currently lacking.

Objectives

This study aims to contribute to a better understanding of the prevalence, risk factors and mental health impact of SV in a gerontopsychiatric patient population.

Methods

Between July 2019 and March 2020 100 patients (66%F, 34%M) participated in a face to face interview on health, sexuality and wellbeing during their admission at an old age psychiatry ward in one general hospital and two psychiatric hospitals across Flanders, Belgium. Participation rate was 58%. Interviews were performed by a psychiatric trainee and especially trained master students in medicine.

Results

58% (65%F; 42%M) of the participants were sexually victimised during their life, 45% (51%F, 33%F) experienced hands-off SV, 43% (48%F, 33%M) sexual abuse with physical contact and 16% (6%M, 21%F) was raped. 7% were sexually victimised in the past year. Compared with non-victimized respondents, hands-on SV victims (incl. rape) described more symptoms of depression (p=0.007) and anxiety (p=0.003) and reported lower resilience (p=0.022).

Conclusions

SV appears to be common in the gerontopsychiatric population and is linked to even worse mental health outcomes. These findings confirm the long-lasting mental health impact of SV and highlight the importance of attention to (sexual) trauma in mental health care in old age.

Disclosure

No significant relationships.

[Repetitive inappropriate sexual behaviour as a symptom of agitated depression: catatonic stereotypy?]

Catatonia is a psychomotor syndrome characterised by multiple symptoms like stereotypies - repetitive, abnormally frequent, non-goal-directed movements. A problem is the lack of unanimity regarding the number of symptoms needed for diagnosis. We describe repetitive inappropriate sexual behaviour in a patient with bipolar depression and excited catatonia with Bush-Francis Catatonia Rating Scale score of 12. Electroconvulsive therapy resulted in disappearance of catatonia and inappropriate sexual behaviour and remission of depression. A recurrent episode with similar inappropriate sexual behaviour was successfully treated with electroconvulsive therapy. We interpreted the repetitive inappropriate sexual behaviour as a catatonic stereotypy. Similar stereotypies are reported in children with autism. Tics and self-injury in patients with autism are described as a stereotypy within catatonia. The agitated depression is another possible diagnosis with the repetitive inappropriate sexual behaviour as an example of psychomotor agitation. More research is needed towards repetitive inappropriate sexual behaviour as a possible stereotypy within catatonia.

Psychosocial outcomes 3 years after facial transplantation of a blind patient

Background

To date, psychosocial outcomes after facial transplantation are promising although long-term consequences, outcome of blind patients and the impact on family members are less well investigated. The aim of this study was to examine the long-term psychosocial of a blind patient and his partner 2 and 3 years after facial transplantation.

Methods

Depressive and anxiety symptoms, hopelessness, coping, resilience, illness cognitions, marital support, dyadic adjustment, family functioning and quality of life of the patient and the partner were assessed before and 2 and 3 years after transplantation. Reliable change index (RCI) was further calculated to evaluate the magnitude of change.

Results

Most psychological, marital and family scores of both the patient and the partner remained within a normative and healthy range at follow-up. Resilience (RCI: 2.5 & 3.4 respectively), affective responsiveness (RCI: −4.1 & −3.2 respectively), physical quality of life (RCI: 8.7 & 7.2 respectively) and helplessness (RCI: −2.2 & −2.9 respectively) of the patient improved at 2 and 3 years follow-up. Further, dyadic cohesion (RCI: 2.4) of the patient improved at 2 years whereas marital depth (RCI: −2.0) of the partner decreased at 3 years.

Conclusions

The results of this study point to positive long-term psychosocial outcomes of a blind patient and his partner after facial transplantation. Further, they may underscore the importance of patient selection, social support and involvement of family members in treatment.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Thrombolytic and Pharmacokinetic Properties of a Recombinant Chimeric Plasminogen Activator Consisting of a Fibrin Fragment D-Dimer Specific Humanized Monoclonal Antibody and a Truncated Single-Chain Urokinase

A recombinant chimeric plasminogen activator consisting of a humanized monoclonal antibody specific for cross-linked human fibrin (MA-15C5Hu) and a 32 kDa single-chain urokinase-type plasminogen activator (scu-PA-32k) comprising amino acids Leu144-Leu411, MA-15C5Hu/scu-PA-32k, was previously found to have a 12-fold higher fibrinolytic potency than recombinant scu-PA-32k towards a human plasma clot in a human plasma milieu in vitro (Vandamme et al., Eur J Biochem 1992; 205: 139–46). Therefore, the thrombolytic and pharmacokinetic properties of MA-15C5Hu/scu-PA-32k were compared with those of recombinant single-chain urokinase-type plasminogen activator (scu-PA) in 3 different venous thrombosis models in vivo. In hamsters with a pulmonary embolus consisting of a human plasma clot, the thrombolytic potency (% lysis per dose in mg/kg administered) of MA-15C5Hu/scu-PA-32k was 23-fold higher than that of scu-PA (p <0.0005). In rabbits with a jugular vein clot prepared from human plasma, the thrombolytic potency of MA-15C5Hu/scu-PA-32k was 11-fold higher than that of scu-PA (p = 0.012). In baboons with an autologous whole blood clot in the femoral vein, the chimera had a 5-fold higher thrombolytic potency than scu-PA. In all three animal species, the clearance of the chimera was 10- to 27-fold reduced as compared to scu-PA. The specific thrombolytic activity (% lysis per µg/ml steady-state plasma u-PA antigen) was increased up to 7-fold with MA-15C5Hu/scu-PA-32k as compared with scu-PA, which is indicative of targeting of the chimera to the clot. No fibrinogen breakdown or α2-antiplasmin depletion was observed during thrombolysis with the chimera.

Thus, MA-15C5Hu/scu-PA-32k constitutes a recombinant chimeric plasminogen activator with a significantly enhanced thrombolytic potency in 3 different animal models of venous thrombosis.

Modulation of Cell-associated Plasminogen Activation by Stromelysin-1 (MMP-3)

Stromelysin-1 (MMP-3) cleaves a 55 kDa kringle 1-4 fragment, containing the lysine-binding site(s) involved in cellular binding, from 92 kDa plasminogen and removes a 17 kDa NH2-terminal fragment, containing the cellular receptor-binding site, from 45 kDa urokinase (u-PA), but a potential role of MMP-3 in the regulation of cellular fibrinolytic activity by affecting binding and/or activation of plasminogen and/or single-chain u-PA has not been established. Human plasminogen (input concentration 100 nM for 4 × 106 cells per ml) was shown to bind specifically to human monocytoid THP-1 cells, to murine MMP-3 deficient smooth muscle cells (SMC) and fibroblasts (1.9, 0.92 and 1.0 × 106 molecules per cell, respectively). Treatment with MMP-3 (final concentration 0-50 nM) of cells saturated with bound plasminogen (about 25 nM), overnight at 37° C, resulted in a dose-dependent reduction of the amount of u-PA activatible plasminogen (reduction to 25-40% of the value in the absence of MMP-3). Immunoblotting with specific monoclonal antibodies and autoradiography of eluates of the cells treated with MMP-3 revealed cleavage of plasminogen into the 55 kDa fragment and miniplasminogen (kringle 5 plus the proteinase domain).

Binding of human single chain u-PA (scu-PA) to human THP-1 and HT 1080 cells amounted to 2.5 × 106and 7.1 × 106 molecules per cell, respectively. Treatment with MMP-3 (final concentration 0-25 nM) of cell-bound u-PA (about 17 nM for THP-1 and 47 nM for HT1080 cells), overnight at 37° C, did not alter cell-associated u-PA activity, measured in a direct chromogenic substrate assay or in a plasminogen-coupled chromogenic substrate assay (residual u-PA activity always ≥85% of that without MMP-3 treatment). Autoradiography of 125I-labeled u-PA moieties, removed from the cells by treatment with acid or with phosphatidylinositol phospholipase C, confirmed that u-PA remained essentially intact after MMP-3 treatment.

These data indicate that MMP-3 may downregulate cell-associated plasmin activity by decreasing the amount of activatible plasminogen, without affecting cell-bound u-PA activity.

Regulation of Gelatinase Activity in Mice with Targeted Inactivation of Components of the Plasminogen/Plasmin System

To investigate a potential physiological role of the plasminogen/ plasmin system in activation of the matrix metalloproteinase (MMP) system, the distribution of latent and active MMP-2 (gelatinase A) or MMP-9 (gelatinase B) was monitored in aorta extracts and in serum-free conditioned cell culture medium obtained from wild-type (WT) mice and from mice with deficiency of tissue-type plasminogen activator (t-PA–/–), urokinase-type plasminogen activator (u-PA–/–), plasminogen activator inhibitor-1 (PAI-1–/–) or plasminogen (Plg–/–).

In aorta extracts, the contribution of active MMP-2 to the total MMP-2 level ranged between 7 and 16% for the different genotypes, whereas active MMP-9 was not detected.

The contribution of active 58 kDa MMP-2 to the total MMP-2 level (active plus latent) ranged between 14 and 29% (mean of 3 experiments) for fibroblasts of the different genotypes, and between 18 and 32% for smooth muscle cells, and was relatively constant in time (7-72 h). The contribution of active 83 kDa MMP-9 to the total MMP-9 level ranged between 15 and 29% for fibroblasts of the different genotypes and was relatively constant in time (24-72 h); corresponding values were 17 to 57% for smooth muscle cells, with the exception of Plg–/– smooth muscle cells which had undetectable levels of active MMP-9. Addition of plasmin(ogen) to the cell culture medium of fibroblasts did not significantly affect the distribution of active and latent MMP-2, but resulted in an approximately two-fold enhancement of the contribution of active MMP-9. In macrophages of Plg–/– mice, active MMP-9 was detected only when the cells were cultured in the presence of plasminogen.

These data indicate that activation of proMMP-2 occurs independently of the physiological plasminogen activators and of plasmin(ogen) in all the cell types evaluated. Activation of proMMP-9 was enhanced in the presence of plasmin(ogen), but active MMP-9 was also detected in fibroblasts of Plg–/– mice, indicating that in vivo activation may occur via plasmin(ogen)-independent mechanisms.

[Non-invasive neurostimulation in the treatment of child and adolescent psychiatry]

Neurostimulation is a potentially interesting treatment option for children and adolescents with psychiatric disorders.<br/> AIM: To review the efficacy of two non-invasive neurostimulation techniques, namely repetitive transcranial magnetic stimulation (rtms) and transcranial direct current stimulation (tdcs), in the treatment of child and adolescent psychiatric disorders.<br/> METHOD: We searched the literature research using PubMed.<br/> RESULTS: There is some evidence that rtms is being used to treat unipolar depression, psychosis, autism spectrum disorder, attention deficit hyperactivity disorder and tic disorder. So far, however, very little research has been done on tdcs.<br/> CONCLUSION: Further research is vitally important in order to ensure the safety and efficacy of rtms and tdcs.

An alpha-mercaptoacrylic acid derivative (PD150606) inhibits selective motor neuron death via inhibition of kainate-induced Ca2+ influx and not via calpain inhibition

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by selective motor neuron death. The exact mechanism responsible for this selectivity is not clear, although it is known that motor neurons are very sensitive to excitotoxicity. This high sensitivity is due to a high density of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors on their surface and to a limited Ca(2+) buffering capacity. Ca(2+) can enter the cell upon stimulation through voltage-operated Ca(2+) channels and through the Ca(2+)-permeable portion of AMPA receptors. How this Ca(2+) kills motor neurons is incompletely understood. In the present study, we report that kainate (KA)-induced motor neuron death is purely mediated through Ca(2+) entering motor neurons through Ca(2+)-permeable AMPA receptors and that voltage-operated Ca(2+) channels play no significant role. In contrast to what has been observed in other neuronal models or after N-methyl-D-aspartate stimulation, NO synthase inhibition and a number of antioxidants did not protect motor neurons from KA-induced death. Only PD150606, derived from alpha-mercaptoacrylic acid and considered as a selective calpain antagonist, inhibited dose-dependently the KA-induced motor neuron death. However, other calmodulin and calpain inhibitors were not effective. At least part of the inhibitory effect of PD150606 is due to an irreversible inhibition of the Ca(2+) influx through the Ca(2+)-permeable AMPA receptor. These results demonstrate the interesting property of PD150606 to interfere with excitotoxicity-dependent motor neuron death and show that PD150606 is not an exclusive calpain/calmodulin antagonist.

Matrix metalloproteinase deficiencies do not impair cell-associated fibrinolytic activity

The matrix metalloproteinase (MMP) and fibrinolytic (plasminogen/plasmin) systems cooperate in many (patho)physiological processes requiring extracellular proteolysis. The effect of MMP-3 (stromelysin-1), MMP-7 (matrilysin), MMP-9 (gelatinase B) or MMP-12 (metalloelastase) on cellular fibrinolytic activity was studied with the use of smooth muscle cells (SMC) and fibroblasts derived from mice with specific inactivation of these genes. Activation of cell-bound plasminogen by two-chain urokinase-type plasminogen activator (tcu-PA) was not significantly different with SMC or fibroblasts from the gene-deficient mice (78% to 140% of wild-type). For all cell types, very limited conversion of plasminogen to angiostatin-like kringle-containing fragments was observed (< 3% of the total cell-bound plasminogen). Activation of plasminogen in solution by cell-associated tcu-PA was also comparable for SMC or fibroblasts of the different genotypes (54% to 160% of wild-type). In vitro SMC migration on scrape wounded collagen-coated surfaces was comparable for wild-type, MMP-7(-/-), MMP-9(-/-) and MMP-12(-/-) SMC, but was significantly reduced for MMP-3(-/-) SMC (P < .005 vs. wild-type). Serum-free conditioned medium of MMP-3(-/-) and MMP-7(-/-) SMC or fibroblasts induced similar lysis of fibrin films as wild-type cells. These findings indicate that several interactions that have been described between these MMPs and the plasminogen/plasmin system in a purified system do not significantly affect plasmin-mediated cellular fibrinolytic activity under cell culture conditions.

Modulation of cell-associated plasminogen activation by stromelysin-1 (MMP-3)

Stromelysin-1 (MMP-3) cleaves a 55 kDa kringle 1-4 fragment, containing the lysine-binding site(s) involved in cellular binding, from 92 kDa plasminogen and removes a 17 kDa NH2-terminal fragment, containing the cellular receptor-binding site, from 45 kDa urokinase (u-PA), but a potential role of MMP-3 in the regulation of cellular fibrinolytic activity by affecting binding and/or activation of plasminogen and/or single-chain u-PA has not been established. Human plasminogen (input concentration 100 nM for 4x10(6) cells per ml) was shown to bind specifically to human monocytoid THP-1 cells, to murine MMP-3 deficient smooth muscle cells (SMC) and fibroblasts (1.9, 0.92 and 1.0x10(6) molecules per cell, respectively). Treatment with MMP-3 (final concentration 0-50 nM) of cells saturated with bound plasminogen (about 25 nM), overnight at 37 degrees C, resulted in a dose-dependent reduction of the amount of u-PA activatable plasminogen (reduction to 25-40% of the value in the absence of MMP-3). Immunoblotting with specific monoclonal antibodies and autoradiography of eluates of the cells treated with MMP-3 revealed cleavage of plasminogen into the 55 kDa fragment and miniplasminogen (kringle 5 plus the proteinase domain). Binding of human single chain u-PA (scu-PA) to human THP-1 and HT 1080 cells amounted to 2.5x10(6) and 7.1x10(6) molecules per cell, respectively. Treatment with MMP-3 (final concentration 0-25 nM) of cell-bound u-PA (about 17 nM for THP-1 and 47 nM for HT1080 cells), overnight at 37 degrees C, did not alter cell-associated u-PA activity, measured in a direct chromogenic substrate assay or in a plasminogen-coupled chromogenic substrate assay (residual u-PA activity always > or =85% of that without MMP-3 treatment). Autoradiography of 125I-labeled u-PA moieties, removed from the cells by treatment with acid or with phosphatidylinositol phospholipase C, confirmed that u-PA remained essentially intact after MMP-3 treatment. These data indicate that MMP-3 may downregulate cell-associated plasmin activity by decreasing the amount of activatible plasminogen, without affecting cell-bound u-PA activity.

Functional magnetic resonance imaging neuroactivation studies in normal subjects and subjects with the narcoleptic syndrome. Actions of modafinil

Functional magnetic resonance imaging (fMRI) can be used to detect regional brain responses to changes in sensory stimuli. We have used fMRI to determine the amount of visual and auditory cortical activation in 12 normal subjects and 12 subjects with the narcoleptic syndrome, using a multiplexed visual and auditory stimulation paradigm. In both normal and narcoleptic subjects, mean cortical activation levels during the presentation of periodic visual and auditory stimulation showed no appreciable differences with either age or sex. Normal subjects showed higher levels of visual activation at 10:00 hours than 15:00 hours, with a reverse pattern in narcoleptic subjects (P = 0.007). The group differences in spatial extent of cortical activation between control and narcoleptic subjects were small and statistically insignificant. The alerting action, and imaging response, to a single oral dose of the sleep-preventing drug modafinil 400 mg were then determined and compared with placebo in both the 12 normal (8 given modafinil, 4 placebo) and 12 narcoleptic subjects (8 modafinil, 4 placebo). Modafinil caused an increase in self-reported levels of alertness in 7 of 8 narcoleptic subjects, but there was no significant difference between mean pretreatment and post-treatment activation levels as determined by fMRI for either normal or narcoleptic syndrome subjects given modafinil. However, in the modafinil-treated group of 8 normal and 8 narcoleptic subjects, there was a clock time independent correlation between the initial level of activation as determined by the pretreatment scan and the post-treatment change in activation (visual, P = 0.002; and auditory, P = 0.001). No correlation was observed in placebo-treated subjects (P = 0.99 and 0.77, respectively). Although limited by the small number of subjects, and the lack of an objective measure of alertness, the findings of this study suggest that low cortical activation levels in both normal and narcoleptic subjects are increased following the administration of modafinil. Functional magnetic resonance imaging may be a valuable addition to established studies of attention.

Regulation of gelatinase activity in mice with targeted inactivation of components of the plasminogen/plasmin system

To investigate a potential physiological role of the plasminogen/plasmin system in activation of the matrix metalloproteinase (MMP) system, the distribution of latent and active MMP-2 (gelatinase A) or MMP-9 (gelatinase B) was monitored in aorta extracts and in serum-free conditioned cell culture medium obtained from wild-type (WT) mice and from mice with deficiency of tissue-type plasminogen activator (t-PA(-/-)), urokinase-type plasminogen activator (u-PA(-/-)), plasminogen activator inhibitor-1 (PAI-1(-/-)) or plasminogen (Plg(-/-)). In aorta extracts, the contribution of active MMP-2 to the total MMP-2 level ranged between 7 and 16% for the different genotypes, whereas active MMP-9 was not detected. The contribution of active 58 kDa MMP-2 to the total MMP-2 level (active plus latent) ranged between 14 and 29% (mean of 3 experiments) for fibroblasts of the different genotypes, and between 18 and 32% for smooth muscle cells, and was relatively constant in time (7-72 h). The contribution of active 83 kDa MMP-9 to the total MMP-9 level ranged between 15 and 29% for fibroblasts of the different genotypes and was relatively constant in time (24-72 h); corresponding values were 17 to 57% for smooth muscle cells, with the exception of Plg(-/-) smooth muscle cells which had undetectable levels of active MMP-9. Addition of plasmin(ogen) to the cell culture medium of fibroblasts did not significantly affect the distribution of active and latent MMP-2, but resulted in an approximately two-fold enhancement of the contribution of active MMP-9. In macrophages of Plg(-/-) mice, active MMP-9 was detected only when the cells were cultured in the presence of plasminogen. These data indicate that activation of proMMP-2 occurs independently of the physiological plasminogen activators and of plasmin(ogen) in all the cell types evaluated. Activation of proMMP-9 was enhanced in the presence of plasmin(ogen), but active MMP-9 was also detected in fibroblasts of Plg(-/-) mice, indicating that in vivo activation may occur via plasmin(ogen)-independent mechanisms.

Proton spectroscopy in the narcoleptic syndrome. Is there evidence of a brainstem lesion?

There is controversy regarding the relationship of structural or biochemical brainstem lesions to "idiopathic" narcolepsy. Most cases of the narcoleptic syndrome are considered to be idiopathic because no structural lesion is detectable, although some cases of secondary narcolepsy are known to be associated with no structural brainstem lesions. Using proton spectroscopy, we determined levels of ventral pontine metabolite pools in 12 normal subjects and 12 subjects with idiopathic narcolepsy. REM sleep is generated in ventral pontine areas. Proton spectroscopy was used to study levels of N-acetyl aspartate (NAA) as a marker of cell mass, creatine and phosphocreatine (Cr + PCr), and choline (Cho). The intensity of the peaks, as determined by the area under the peak (AUP), was measured. The AUP correlates with the quantity of chemical present. In this study, the ratios of NAA to Cr + PCr were similar in normal subjects and in narcoleptic subjects with idiopathic narcolepsy. No differences in measured metabolic ratio were observed in subjects who slept during the scan procedure compared with those who remained awake. Subjects with "symptomatic" narcolepsy accompanied by an obvious structural brain lesion were not studied. Proton spectroscopy of the brain initiates a new kind of neurochemistry, allowing the noninvasive study of metabolic pools in the living human brain without the use of any kind of tracer or radioactive molecule. In this study, there was no evidence of cell loss in the ventral pontine areas of subjects with the narcoleptic syndrome.

Changes in putamen N-acetylaspartate and choline ratios in untreated and levodopa-treated Parkinson's disease: a proton magnetic resonance spectroscopy study

We have carried out single-voxel proton magnetic resonance spectroscopy centered on the putamen both ipsilateral and contralateral to the worst affected side in nine subjects with drug naive idiopathic Parkinson's disease (IPD); seven chronically levodopa-treated dyskinetic IPD subjects; and 11 age-matched healthy controls. Measurements of N-acetylaspartate (NAA)/choline (Cho), NAA/(Creatine + Phosphocreatine) (Cr + PCr), and Cho/(Cr + PCr) were made. We found a significant reduction in NAA/Cho ratios from the putamen contralateral to the most affected side in the drugnaive group (p = 0.009), but not the levodopa-treated IPD groups compared with controls. There were no significant differences in NAA/(Cr + PCr) or Cho/(Cr + PCr) ratios. In untreated IPD, reduced putaminal NAA/Cho ratios may reflect loss of nigrostriatal dopamine terminals or alternatively indicate a functional abnormality of striatal putaminal neurons, such as membrane dysfunction due to striatal deafferentation. This study suggests that NAA/Cho ratios may be affected by L-dopa therapy and this may provide a reversible marker of neuronal dysfunction in the striatum.

Melatonin and insomnia

The hypnotic action of melatonin 5 mg p.o. was explored in 15 subjects with psychophysiological insomnia in a double-blind controlled self-report questionnaire study. Melatonin or placebo was taken at 20.00 hours for a 1-week period in random order. Effects on sleep and wakefulness were monitored by visual analogue scale and structured interview. Bedtime, sleep onset time, estimated total sleep and wake time, as well as self-rated sleep quality, were not altered by melatonin, and estimates of next-day function did not change. The period of melatonin, treatment was retrospectively correctly identified by 8 of 15 subjects. Despite unchanged ratings of night sleep quality on the last night of each treatment, 7 of 15 subjects reported that sleep had subjectively improved to a minor extent in the week of active treatment. Side-effects attributed to melatonin included headache and an odd taste in the mouth. These data indicate that melatonin is probably of no clinical value in the management of psychophysiological insomnia.

Pre-sleep behaviour in normal subjects

Behaviour in the 2-h period before sleep onset was evaluated in 90 subjects with normal sleep/wake habits using an anonymous self-report questionnaire. This determined the timing of events from the initial preparation for sleep. The nature of the pre-sleep environment, the level of physical activity, and patterns of feeding behaviour were recorded together with self-ratings of tiredness, mood and security. Estimated sleep duration and sleep quality were determined. Ninety of 120 subjects responded. Sleep 'preparatory latency', from the time of initial sleep preparation to sleep onset, was 77 +/- 48 min; bed time to sleep onset time (sleep latency) was 41 +/- 42 min; lights out to sleep onset latency was 26 +/- 45 min. The estimated total sleep time was 7 +/- 1 h. In the pre-sleep period, mean noise and illumination levels were low and environmental temperature rating was at the median point on a very cold-very hot scale (mean scale scores: 23, 28 and 50, respectively). All subjects went to the bathroom before going to bed. Twenty-five percent of normal subjects had a snack or meal in the 2-h period before sleep onset. Sixty percentage recorded setting an alarm, 27% had a bath or shower, 23% checked door locks or windows and 49% read in bed. Nine percent of subjects slept with a cat on the bed. Humans, like other animal species, show a complex behavioural sequence in the 2-h period before falling asleep. A constant environment with limited metabolic activity may predispose to thermoregulatory changes prior to sleep onset.

Immunohistochemical staining of ras oncogene product in neoplastic and non-neoplastic mesothelial tissues: immunoreactivity for N-ras and lack of immunohistochemical staining for Ha-ras and K-ras

Immunohistochemical staining of 36 malignant mesotheliomas and 45 cases of non-neoplastic mesothelium including 20 specimens with signs of hyperplasia were investigated using murine monoclonal antibodies directed against p21 ras protein, Ha-ras protein, K-ras protein, and N-ras protein. All cases of non-neoplastic mesothelium and the majority of the malignant mesotheliomas (78 per cent) showed cytoplasmic and often submembranous immunoreactivity in more than 50 per cent of the cells with both the pan-ras and N-ras antibody. No immunoreactivity was observed for Ha- and K-ras. There was no statistically significant difference with respect to immunoreactivity between neoplastic and non-neoplastic mesothelium or between the various mesothelioma subtypes.

Immunoreactivity for p53 protein in malignant mesothelioma and non-neoplastic mesothelium

The presence of p53 protein in non-neoplastic pleural mesothelium (40 cases) and in human malignant mesothelioma (36 cases) was assessed immunohistochemically using the antibodies DO7, CM-1, and PAb240. In a quarter of the malignant mesotheliomas, there was nuclear immunoreactivity for p53 protein with both the DO7 and CM-1 antibodies. There were no statistically significant differences between the various mesothelioma subtypes (P > 0.05). No immunoreactivity was found with the PAb240 antibody, suggesting absence of mutant-type p53 protein. Nonneoplastic mesothelium was not immunoreactive with any of the antibodies. We conclude that there is immunoreactivity for p53 protein in some mesotheliomas. p53 protein immunoreactivity could be used to discriminate between neoplastic and reactive mesothelium.

Thrombolytic and pharmacokinetic properties of a recombinant chimeric plasminogen activator consisting of a fibrin fragment D-dimer specific humanized monoclonal antibody and a truncated single-chain urokinase

A recombinant chimeric plasminogen activator consisting of a humanized monoclonal antibody specific for cross-linked human fibrin (MA-15C5Hu) and a 32 kDa single-chain urokinase-type plasminogen activator (scu-PA-32k) comprising amino acids Leu144-Leu411, MA-15C5Hu/scu-PA-32k, was previously found to have a 12-fold higher fibrinolytic potency than recombinant scu-PA-32k towards a human plasma clot in a human plasma milieu in vitro (Vandamme et al., Eur J Biochem 1992; 205: 139-46). Therefore, the thrombolytic and pharmacokinetic properties of MA-15C5Hu/scu-PA-32k were compared with those of recombinant single-chain urokinase-type plasminogen activator (scu-PA) in 3 different venous thrombosis models in vivo. In hamsters with a pulmonary embolus consisting of a human plasma clot, the thrombolytic potency (% lysis per dose in mg/kg administered) of MA-15C5Hu/scu-PA-32k was 23-fold higher than that of scu-PA (p less than 0.0005). In rabbits with a jugular vein clot prepared from human plasma, the thrombolytic potency of MA-15C5Hu/scu-PA-32k was 11-fold higher than that of scu-PA (p = 0.012). In baboons with an autologous whole blood clot in the femoral vein, the chimera had a 5-fold higher thrombolytic potency than scu-PA. In all three animal species, the clearance of the chimera was 10- to 27-fold reduced as compared to scu-PA. The specific thrombolytic activity (% lysis per micrograms/ml steady-state plasma u-PA antigen) was increased up to 7-fold with MA-15C5Hu/scu-PA-32k as compared with scu-PA, which is indicative of targeting of the chimera to the clot. No fibrinogen breakdown or alpha 2-antiplasmin depletion was observed during thrombolysis with the chimera. Thus, MA-15C5Hu/scu-PA-32k constitutes a recombinant chimeric plasminogen activator with a significantly enhanced thrombolytic potency in 3 different animal models of venous thrombosis.

K1K2Pu, a recombinant t-PA/u-PA chimera with increased thrombolytic potency, consisting of amino acids 1 to 3 and 87 to 274 of human tissue-type plasminogen activator (t-PA) and amino acids 138 to 411 of human single chain urokinase-type plasminogen activator (scu-PA). Purification in centigram quantities and conditioning for use in man

K1K2Pu, a recombinant t-PA/u-PA chimera with increased thrombolytic potency in animal models of venous and arterial thrombosis, which consists of amino acids 1 to 3 and 87 to 274 of human tissue-type plasminogen activator (t-PA) and amino acids 138 to 411 of human single chain urokinase-type plasminogen activator (scu-PA), was produced and conditioned for use in patients. Chinese hamster ovary cells were transfected with an expression plasmid containing the K1K2Pu cDNA, high producer cell lines were selected and scaled up in 800 cm2 roller bottles, and 350 ml conditioned cell culture medium was harvested 3 to 7 times at 2 to 5 day intervals. Batches of 21 +/- 4 liter (mean +/- SD, n = 28) containing 1.8 +/- 0.6 mg/l of K1K2Pu related antigen were purified by chromatography on Copper chelate-Sepharose and immunoadsorption on an insolubilized murine monoclonal antibody (MA-1C8). Yields were 8.6 +/- 3.4 mg K1K2Pu per batch with a specific activity of 83,000 +/- 44,000 IU/mg. The final material, obtained at a concentration of approximately 0.7 mg/ml, was dialyzed against 0.3 M NaCl, 0.02 M Tris-HCl buffer, pH 7.5, containing 0.01% Tween 80 and 10 KIU/ml aprotinin. It was homogeneous on SDS-PAGE, contained 6.5 +/- 6.9 percent two chain material and the contamination with murine monoclonal antibody was less than 0.1 percent. After filtration of pools of 3 to 5 selected batches on 0.22 microns Millipore filters the material was sterile and virus free by routine screening; it was obtained at a concentration of approximately 0.5 mg/ml with a specific activity of 110,000 +/- 16,000 IU/mg (mean +/- SD, n = 3) and an endotoxin content of 0.5 to 7 units/mg. Bolus injection at a dose of 1 mg/kg in mice did not produce weight loss within 8 days. Thus, this material appears to be suitable for the investigation on a pilot scale of the pharmacokinetic and thrombolytic properties of K1K2Pu in patients with thromboembolic disease.