Robot-guided osteotomy in fibula free flap mandibular reconstruction: a preclinical study

Various methods currently exist to guide fibular osteotomy positioning in fibula free flap mandibular reconstruction, but patient-specific navigation methods and cutting guides require experience, and may be time-consuming and/or expensive. This study describes a robot-guided osteotomy technique for mandible reconstruction using a fibula free flap according to virtual preoperative planning. The method was assessed on five 3D-printed models and a cadaveric model. The precision of the robot-guided osteotomy was evaluated by measuring the deviations between the lengths and angles of the fragments obtained and those of the virtual planning. The average deviation of the anterior and posterior crest lengths was 0.42 ± 0.29 mm for the 3D-printed models and 1.00 ± 0.53 mm for the cadaveric model. The average angle deviation was 1.90 ± 1.22° and 1.94 ± 0.69° for the 3D-printed and cadaveric models, respectively. The results of this preclinical study revealed that fibular osteotomy positioning guidance using a robot-positioned cutting guide may be a precise, easy-to-use technique that could be tailored for fibula free flap mandibular reconstruction.

[Two experimental models for wound vitality evaluation in forensic pathology: A clinical prospective non-interventional study and an animal model]

AIM OF THE STUDY

In forensic pathology, wound age evaluation allows to determine if a wound was inflicted before or after death, and to date wounds of different ages. This dating is performed in conventional histopathology by observing inflammatory cells and hemorrhage at the wound site. However, these criteria seem to show low sensitivity and/or specificity. The aim of our study was to compare two models of wound vitality evaluation: a human surgical model, and a porcine experimental model; using these histological criteria.

PATIENTS AND METHOD

In the two human (n=38) and porcine (n=11) models, three wounds were performed at regular time-lapse before devascularization/sacrifice, and a control wound after devascularization/sacrifice. The main evaluation criteria were the presence of interstitial hemorrhage and the number of interstitial polymorphonuclear neutrophils at 10 high power fields.

RESULTS

In the two models, the number of polymorphonuclears neutrophils was significantly higher in vital wounds compared to the post-devascularization/sacrifice wounds (P<0.001), with a very low sensitivity (human model: 4.3%; porcine: 47%). Hemorrhagic infiltration was more frequent in vital wounds (human: P<0.001; porcine: P=0.01), with a low specificity (human: 48%; porcine: 54%).

DISCUSSION AND CONCLUSION

This first study confirms, in the two models, the limitations of conventional histopathology in wound vitality evaluation. The next step will be testing several immunohistochemical markers in the two models.

First year of pre-exposure prophylaxis implementation in France with daily or on-demand tenofovir disoproxil fumarate/emtricitabine

BACKGROUND

In January 2016, the French Medicine Agency initiated a Temporary Recommendation for Use (TRU) to allow the use of oral intake of tenofovir disoproxil fumarate and emtricitabine for pre-exposure prophylaxis (PrEP) in adults at high risk of HIV. We report the results of the first year of PrEP implementation in France.

METHODS

Data were collected by physicians using a secured web subject-monitoring interface, with two forms: an initiation form, with patients' baseline characteristics, and an HIV seroconversion form. Univariate and adjusted multivariate analysis using a logistic regression model were performed to identify baseline factors associated with on-demand PrEP regimen prescription.

RESULTS

From 4 January 2016 to 28 February 2017, 3405 subjects were enrolled, with 2774 initiation forms completed; 98.1% were male and 96.9% were MSM. An on-demand regimen was prescribed to 57% of subjects. Older age (OR for participants older than 50 years = 1.76, 95% CI 1.35-2.3, P < 0.001) and site of prescription (OR of former IPERGAY sites = 2.28, 95% CI 1.84-2.83, P < 0.001) were associated with on-demand prescription. Those reporting sexually transmitted infection (STI) and condomless anal sex with at least two different partners were less likely to receive on-demand PrEP (OR = 0.68, 95% CI 0.57-0.82 and 0.75, 95% CI 0.57-0.98, respectively; P < 0.05 for all). Four breakthrough HIV infections were reported during the study, in the context of PrEP interruption or acute infection at the time of PrEP initiation.

CONCLUSIONS

In a real-life setting in France, PrEP was used, either daily or on-demand, mostly by MSM, with breakthrough infections being rare.

Arousal, EEG spectral power and pulse transit time in UARS and mild OSAS subjects

OBJECTIVES

Upper airway resistance syndrome (UARS) and obstructive sleep apnea syndrome (OSAS) are associated with arousals and autonomic activation. Pulse transit time (PTT) has been used to recognize transient arousals. We examined the accuracy of PTT to recognize arousals, and the relationship between PTT deflection and visual and non-visual arousals.

METHODS

Ten UARS and 10 mild OSAS subjects were studied via polysomnography including measurement of esophageal pressure. Electroencephalogram (EEG) spectral power was obtained from central leads. Seven types of events were identified, depending upon the presence or absence of: a sleep-related respiratory event (SRRE), i.e. apnea, hypopnea, and abnormal breathing effort; a PTT signal; or a visually scored arousal (>1.5s).

RESULTS

One thousand four hundred forty-six events were identified in 20 subjects. Fifty-nine percent of all SRREs were associated with a PTT signal and a visual EEG arousal. Nineteen percent of SRREs had no EEG arousals at their termination, and 7.4% had no associated PTT signal. Delta power was significantly increased when non-visual EEG arousals were scored. The time delay for PTT was determined by the presence or absence of EEG arousal. The sensitivity of PTT to recognize EEG arousal was 90.4% and the specificity was 16.8%. The sensitivity and specificity of PTT to recognize SRRE was 90.7 and 21.9%, respectively.

CONCLUSIONS

These results preclude the use of PTT by itself. SRREs induce an activation with positive PTT response but without arousal in 14% of cases. This PTT response, however, is much slower than that occurring with arousal. UARS and mild OSAS do not respond in the same way to SRREs, particularly during rapid eye movement sleep.

Sleep-disordered breathing and upper-airway anomalies in first-degree relatives of ALTE children

From 1985 through 1995, 348 infants aged 3 wk-3 mo were referred to the Stanford Sleep Clinic for "apparent life-threatening events" (ALTE). A small group of 48 infants with no history of sleep-disordered breathing (SDB) was also recruited and used as controls (they comprised group C). We conducted a systematic investigation of relatives (parents, siblings, and grandparents) of the infants, including a clinical evaluation, craniofacial investigation, and the completion of an extensive (189-question) validated sleep/wake questionnaire. All data were calculated before the subdivision of ALTE infants into two groups. The subdivision was based on a blind scoring of the infants' polygraphic recordings; 42.5% of the infants were negative for SDB (Group A), whereas 57.5% of the infants were positive for SDB (Group B). Groups A and C were not significantly different from each other. Forty-three percent of the relatives of Group B infants had been treated for SDB (with nasal CPAP, surgical or dental appliance treatments) compared with 7.1% of Group A relatives. Clinical investigation indicated a significantly higher presence of small upper airways in the families of infants with SDB. About twice as many relatives reported the presence of asthma in Group B compared with Group A. Naso-oro-maxillomandibular anatomic traits that may lead to small upper airways in parents may be risk factors for abnormal breathing during sleep in their infants.

Sleep and daytime sleepiness in upper airway resistance syndrome compared to obstructive sleep apnoea syndrome

This study has investigated differences in the nocturnal sleep and daytime sleepiness among patients with obstructive sleep apnoea syndrome (OSAS), upper airway resistance (UARS), sleep hypopnoea syndrome, and normal control subjects, using sleep scoring and spectral activity analysis of the electroencephalogram (EEG). Twelve nonobese males with UARS aged 30-60 yrs were recruited. These subjects were strictly matched for age and body mass index with twelve OSAS patients, 12 sleep hypopnoea syndrome patients, and 12 normal controls, all male. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS) and the Multiple Sleep Latency Test (MSLT). The macrostructure of sleep was determined using international criteria and spectral analysis of the sleep EEG was obtained from a central lead. The sleep macrostructure of OSAS and UARS patients was significantly different from that of controls. These patients were also sleepier during the daytime than controls. Complaints of tiredness and daytime sleepiness, ESS and MSLT scores were similar in the different patient groups. Mild dysmorphia was present in all three patient groups. However, nocturnal sleep was significantly different among the different groups. OSAS patients had significantly more awake time during sleep than the UARS patients. The spectral activity of the total sleep time of the patient groups also differed significantly from that of controls. When the sleep spectral activity of UARS and OSAS patients were compared, OSAS patients had less slow wave sleep activity than UARS patients. UARS patients had a significantly higher absolute power in the 7-9 Hz bandwidth than OSAS patients. The absolute delta power over the different sleep cycles was also different between controls and patients, and between UARS and OSAS patients. There are clear differences in the macrostructure and spectral activity of sleep between upper airway resistance and obstructive sleep apnoea syndrome patients, demonstrated by differences in the cortical activity recorded in the central lead during sleep. Despite these nocturnal sleep differences, the tests of subjective daytime sleepiness are not significantly different.

Hypoxia-induced loss of synaptic transmission is exacerbated in hippocampal slices of transgenic mice expressing C-terminal fragments of Alzheimer amyloid precursor protein

To investigate the possible involvement of beta-amyloid (A beta) in disrupting neuronal function during ischemia, we examined whether overexpression of C-terminal fragments of beta-amyloid precursor protein (beta-APP) in transgenic (Tg) mice is capable of altering the capacity of hippocampus slices to recover synaptic transmission after transient hypoxic episodes. Recovery of synaptic transmission was monitored in area CA1 of perfused hippocampal slices prepared from both control and Tg mice. The results obtained indicate that hippocampal slices prepared from Tg mice exhibited a much lower level of recovery in synaptic transmission following reoxygenation. This reduction in the capacity of Tg slices to recover from hypoxia-induced impairment of synaptic transmission in the hippocampus does not appear to be related to pre-existing alterations in either functional or biochemical properties of glutamate receptors in Tg mice. The present results provide the first experimental evidence that overexpression of the C-terminal fragment of APP exacerbates functional damage of hippocampal neurons after hypoxic episodes.

Long distance driving and self-induced sleep deprivation among automobile drivers

OBJECTIVE

To evaluate the sleep hygiene and prevalence of sleep deprivation among a large sample of automobile drivers.

DESIGN

From the 15th of June to the 4th of August 1996, with the help of the French highway patrol, we randomly stopped automobile drivers at the toll booths of Bordeaux and Biarritz. All subjects completed a validated questionnaire on sleep/wake habits during the year. After answering the questionnaire, subjects completed a graphic travel and sleep log of the three days preceding the interview.

PARTICIPANTS

We randomly stopped 2196 automobile drivers. Ninety-one percent of the sample (mean age 43 +/- 13 years) agreed to participate in the survey.

RESULTS

Fifty percent of the drivers decreased their total sleep time in the 24 hours before the interview compared with their regular self-reported sleep time. 12.5% presented a sleep debt > 180 minutes, and 2.7% presented a sleep debt > 300 minutes. Being young, commuting to work, driving long distances, starting the trip at night, being an "evening" person, being a long sleeper during the week, and sleeping in on the week-end were risk factors significantly associated with sleep debt.

CONCLUSION

The results of the study highlight variables (long-distance driving, youth, sleep restriction) that are frequently associated with sleep-related accidents.

AMPA receptor properties in adult rat hippocampus following environmental enrichment

In adult rats, environmental enrichment has been shown to selectively increase -AMPA binding in the hippocampus but the molecular mechanisms underlying this effect remain unknown. We used in situ hybridization with antisense oligonucleotides to determine possible changes in the hippocampal expression of messenger RNAs for different subunits of AMPA receptors in adult rats following exposure to an enriched environment. Quantitative analysis revealed that mRNA levels for three subtypes of AMPA glutamate receptors (GluR1-3; Flip and Flop variants) were not modified in any hippocampal region after environmental enrichment. In addition, no differences were detected in the levels of GluR1 and GluR2/3 proteins in Western blots of hippocampal membranes from enriched rats. Nevertheless, quantitative ligand binding autoradiography indicated that environmental enrichment evoked a significant and uniform decrease in the capacity of calcium or phosphatidylserine (PS) to up-regulate -AMPA binding in various hippocampal regions but not in the cerebral cortex. These findings support previous observations suggesting that post-translational changes in AMPA receptor properties, as a result of the activation of calcium-dependent processes, may represent an important mechanism underlying long-term modifications of synaptic efficacy in the rat hippocampus.

[Instruments to evaluate fitness to stand trial:a review of recent literature]

OBJECTIVES

To present current methods used to assess fitness to stand trial (FST), draw a parallel between these methods and studies of factors associated with decisions regarding FST, and describe the limits inherent to the field of FST.

METHOD

Survey of the relevant literature from Psychinfo and Medline databases from 1967 to 1996 inclusively.

RESULTS

Ten instruments were identified for the systematic collection of information from persons assessed for FST. The description and analysis of their psychometric qualities, however, indicate that these instruments present some problems.

CONCLUSION

Although some research has shown that diagnosis is the factor most associated with decisions regarding FST, no instrument includes a systematic assessment of psychopathology. If we take into account the possible consequences of these decisions for the accused as well as for society, these assessments and the recommendations that follow prove to be extremely important.

Should everyone be monitored for upper-airway resistance and how?

Preliminary data indicate that the use of a morphometric model, an expert system with standardized questions, and an evaluation of snoring can be effective tools for diagnosing upper-airway sleep-disordered breathing (UASDB) in many cases. This eliminates the need for many sleep recordings.

Effect of phosphatidylserine on the binding properties of glutamate receptors in brain sections from adult and neonatal rats

The effects of phosphatidylserine (PS) on the binding properties of the AMPA (alpha-amino-3-hydroxy-5-methylisoxazolepropionic acid) and NMDA (N-methyl-D-aspartate) subtypes of glutamate receptors were analyzed by quantitative autoradiography of [3H]AMPA, [3H]6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and [3H]glutamate binding on rat brain tissue sections. Preincubation of brain sections with PS produced an increase in [3H]AMPA binding without modifying the binding properties of [3H]CNQX, an antagonist of AMPA receptors. This effect of PS appeared to be specific for the AMPA subtype of glutamate receptors as the same treatment did not modify [3H]glutamate binding to the NMDA receptors. Furthermore, the PS-induced increase in [3H]AMPA binding was different in various brain structures, being larger in the molecular layer of the cerebellum and almost absent in the striatum. Preincubation with calcium also augmented [3H]AMPA binding, and the lack of additivity of the effects of calcium and PS on [3H]AMPA binding strongly suggests that both treatments share a common mechanism(s) for producing increased agonist binding. Finally, the effect of PS on AMPA receptor properties was markedly reduced in rat brain sections prepared from neonatal rats at a developmental stage that is normally characterized by the absence of LTP expression in certain brain regions. The present data are consistent with the hypothesis that alteration in the lipid composition of synaptic membranes may be an important mechanism for regulating AMPA receptor properties, which could be involved in producing long-lasting changes in synaptic operation.

[The elderly, sleep habits and use of psychotropic drugs by the French population]

The aging population in western countries and the increase in longevity make the problem of recognition and treatment of sleep disorders more acute in the elderly population. The risk of evolution of sleep disorders in the elderly leads to a greater weakness of their physical health, a greater dependence on their environment, and finally to more frequent recourse to institutionalization. We investigated sleep habits, sleep disorders and psychiatric diagnoses, physical illnesses and psychotropic drug consumption in a representative sample of the general population of France. Interviews were performed over the telephone by lay interviews using the Eval Knowledge Based System, a computerized system that guides the interviewer through the interview process, 6966 subjects were contacted, and 5622 interviews (80.8% of the potential sample) were completed. The sample was divided into four age groups: 15 to 44 years old (56.4%); 45 to 64 years old (25.6%); 65 to 74 years old (10.8%) and 75 years old or more (7.2%). Earlier bedtime, long sleep latency, spending more time in bed with a reduction of nocturnal sleep time, nocturnal awakenings and daytime naps were found more frequently in "young old" (65 to 75 years old) and "old old" subjects (75 years old or more). Daytime naps and spending more time in bed with a reduction of nocturnal sleep time also distinguished "old old" subjects from "young old" subjects. About half of "old old" subjects who complained about their sleep did not get a diagnosis of sleep disorder, nor psychiatric disorder (52.4%). An insomnia diagnosis was given in 14% of cases (mostly primary insomnia-6.7%) and a psychiatric diagnosis in 33.4% of cases (mostly anxiety diagnoses-28.2%). The rate of psychotropic drug consumption was 11.7% (95% Cl: 10.9% to 12.5%) for the entire sample. This consumption dramatically increased with age: 4.8% between 15 to 44 years old; 15.6% between 45 to 64 years old; 24.3% in "young old" subjects and 32.8% in "old old" subjects. Psychotropic drug consumption was distributed as follows: 6.4% of the sample used anxiolytic, 2.7% hypnotic, 1.5% antidepressant and 0.9% hypnotic and anxiolytic together. The chronic use (at least one year) of hypnotic or anxiolytic drugs was frequent in "old old" subjects (92.6% and 80.2%, respectively) and "young old" subjects (74% and 78% respectively). The assessment of sleep by the physician should be made part of the routine clinical examination of older subjects. Review of the etiology of insomnia complaints is crucial in the choice of treatment. The reflex of psychotropic prescription in case of poor sleep is neither sufficient nor desirable, especially because of the risk of chronic use of the prescription. These data underline the importance of educating physicians about consequences of long-term utilization of these drugs and on the need for sleep hygiene measures as alternative solutions for treating insomnia complaints.

Developmental changes in depolarization-mediated AMPA receptor modifications and potassium-induced long-term potentiation

In the present study, we examined the KCl-induced increase in [3H] amino-3-hydroxy-5-methylisoxazole-4-propionate ([3H]AMPA) binding in telencephalic synaptoneurosomes and potentiation of synaptic transmission (KLTP) in hippocampal slices during development in rats. As previously reported, KCI-induced depolarization of telencephalic synaptoneurosomes resulted in a 40 +/- 5% increase in [3H]AMPA binding to membrane fractions in adult rats (3 months old). KCI-induced increase in [3H]AMPA binding was reduced to 24 +/- 5% and 15 +/- 5% at postnatal days (PND) 25-30 and PND 15-20 respectively, and was only 6 +/- 5% at PND 5-10. KLTP in area CA1 of hippocampus was most pronounced in adult slices (40 +/- 5%), and was reduced to 30 +/- 5% in slices prepared from PND 25-30 animals; KCI-induced LTP was absent in CA1 hippocampal slices prepared from PND 5-10 animals (3 +/- 5%). The decrease in KCI-induced changes in AMPA receptor binding in young animals was also associated with an altered capacity of the bee venom peptide, mellitin (a phospholipase A2 (PLA2) activator), to increase [3H]AMPA binding in synaptoneurosomes. The smaller effect of mellitin on [3H]AMPA binding in young animals was not due to a decreased ability of this peptide to release [3H]arachidonate from synaptoneuro-somes. The parallel modifications in the extent of depolarization-induced change in AMPA receptor binding and excitatory synaptic transmission during development further support the hypothesis that alterations in AMPA receptor properties may play a critical role in synaptic plasticity.

Epidemiological study on insomnia in the general population

This study was conducted with a representative sample of the French population of 5,622 subjects of 15 years old or more. The telephone interviews were performed with EVAL, an expert system specialized for the evaluation of sleep disorders. From this sample, 20.1% of persons said that they were unsatisfied with their sleep or taking medication for sleeping difficulties or anxiety with sleeping difficulties (UQS). A low family income, being a woman, being over 65 years of age, being retired and being separated, divorced or widowed are significantly associated with the presence of UQS. A sleep onset period over 15 minutes, a short night's sleep and regular nighttime awakenings are also associated with UQS. Medical consultations during the past 6 months and physical illnesses are more frequent among the UQS group. The consumption of sleep-enhancing medication and medication to reduce anxiety is important: in the past, 16% of subjects had taken a sleep-enhancing medication and 16.2% a medication to reduce anxiety. At the time of the survey 9.9% of the population were using sleep-enhancing medication and 6.7% were using medication for anxiety. For most, hypnotic consumption was long-term: 81.6% had been using it for more than 6 months.

[Abuse of psychotropic drugs during driving]

The responsibility of psychotropic drugs as a cause of road traffic accidents remains difficult to evaluate with precision. Different studies performed in many countries provide a certain precision in relation to percentage of injured drivers whose blood contained psychotropic substances (8 to 10% according to studies). On the other hand, it is practically impossible to really know either these products were or were not the cause of the accidents because underlying or associated pathologies can equally create problems such as lack of attention and other vigilance deficits. There is also a possibility of suicidal or aggressive tendencies. A certain number of circadian and other chronobiological parameters also complicate the problem since the schedule (hour) as well as the day of the week or even the season can considerably modify vigilance and reaction time. Available medications able to create such problems are numerous and their mechanisms of action varied. They can influence vision, impulsiveness and vigilance. They can act either by direct mechanisms of sedation or, on the contrary, by raising inhibition through secondary mechanisms: delay in drug elimination or provoked insomnia. For the most part, incriminated medications belong to the different classes of sedative medicines: benzodiazepines, antiepileptics, some antihistaminic agents, some antidepressants, some thymo-regulators and some anti-hypertensives. Also included are desinhibitors or stimulant classes: amphetamines and related drugs, caffeine and codeine. Some of them can be used for their psychodysleptic properties: codeine and anticholinergic drugs. Finally, drug and medicinal associations can have unforeseen effects: for example, anticholinergics + alcohol + valpromide, etc. If it appears methodologically impossible that research could ever precisely quantify the share of responsibility of psychotropic drugs in causing road traffic accidents, this relation remains highly probable. It is therefore necessary that in the course of university and post-academic training, potential prescribers might regularly be advised of these risks. Lastly, public needs to be constantly informed.

Modulation of the AMPA receptor by phospholipase A2: effect of the antidepressant trimipramine

Previous results have shown that chronic administration of the antidepressant trimipramine prevents the formation of long-term potentiation in the rat hippocampus. In the present study, we compared the effects of chronic administration of trimipramine on the binding properties of hippocampal glutamate receptors and on the modulation of the DL-alpha-amino-3-hydroxy-5- methyl-isoxazolpropionic acid (AMPA) receptors by phospholipase A2 (PLA2). Whereas the binding characteristics of various agonist and antagonist ligands to the N-methyl-D-aspartate and the AMPA receptors were not modified by trimipramine treatment, there was a significant reduction in the increase in 3H-AMPA binding elicited by PLA2 treatment. Since activation of PLA2 has been reported to play a critical role in the formation of long-term potentiation, possibly mediated through a modification of the AMPA receptors, the results strengthen the hypothesis that PLA2-induced modification of 3H-AMPA binding is an important component of synaptic plasticity.

[3H]paroxetine binding and serotonin content of rat brain: absence of changes following antidepressant treatments

The high affinity binding of [3H]paroxetine was measured in rat cerebral cortex following chronic treatment (21 days) with imipramine (5 mg/kg), trimipramine (5 mg/kg) and fluoxetine (2 mg/kg), in adult (3-4 months) or neonatal (7 days of age) rats. Tissue concentrations of serotonin and of its metabolite 5-hydroxyindole-3-acetic acid were also determined by high-performance liquid chromatography in cingulate cerebral cortex, rostral neostriatum, hippocampus and midbrain raphe nucleus region. No differences were found in any of the parameters of [3H]paroxetine binding after antidepressant administration, in either adult or neonatal animals. In addition, endogenous serotonin and 5-hydroxyindole-3-acetic acid levels were not different from control values in any of the regions examined. The present study shows that the serotonin uptake recognition site is resilient to changes after chronic treatment with therapeutic doses of antidepressants, and emphasizes the potential usefulness of uptake site ligands as markers to quantify innervation densities within the brain.

Chronic effects of trimipramine, an antidepressant, on hippocampal synaptic plasticity

The effects of trimipramine (TRIM), an antidepressant agent, on both the induction and the maintenance of long-term potentiation (LTP) was investigated in area CA1 of hippocampal slice preparations. Chronic administration (7-9 days) of TRIM in rat caused a large reduction in the magnitude of LTP induced by a theta burst stimulation (TBS) paradigm. Results indicate that the reduction of LTP produced by trimipramine does not seem to result from major changes in the physiological properties of the slice preparations. First, paired-pulse facilitation was not impaired following the drug administration suggesting that transmitter release was not modified in TRIM-treated slices. Second, the burst responses evoked by high-frequency stimulation exhibited the typical buildup of depolarization, which is due to both a reduction of IPSPs and the activation of NMDA receptors. Finally, the treatment did not change the amount of short-term potentiation induced by TBS nor did it modify the component of excitatory postsynaptic potentials (EPSPs) mediated by the activation of NMDA receptors, suggesting that the NMDA receptor functions remained intact in TRIM-treated slices. Taken together the present data suggest that the loss of LTP maintenance in TRIM-treated animals is more likely the result of the disruption by trimipramine of cellular processes that follow LTP induction. In addition, the results provide evidence for a possible correlation between the reduction in LTP expression and learning deficits produced by chronic administration of trimipramine.

[Use of the Adinfer diagnostic system in a study of somatic disorders in general practice]

Somatic complaints are very common in general medical practice. They are not identified as psychic disorders and are treated symptomatically. We explore two kind of problems: 1. methodological problems such as the instruments to use to examine somatic complaints (it is evident that a checklist does not give the best results with suggestible patients); and 2. the relationships between somatic complaints and psychic disorders such as anxiety, depression and somatoform disorders. Psychiatric nosology is by no means clear and includes many diagnoses from "hysteria" to "hypochondria" or "psychosomatic", "somatization". In this study, we compare the symptoms collected by general practitioners, and their clinical diagnoses to those obtained by an automatic DSM-III diagnostic program. Adinfer was modified so that three DSM decision trees were systematically scanned: depressive, anxiety and somatoform disorders. This allows for an epidemiological study of somatic complaints and their relationship to depression and anxiety. The subjects' score on rating scales for anxiety and depression are compared with the diagnoses made by the expert system. We discuss the significance of somatic symptoms, the DSM classes and the value of expert systems in epidemiological studies.

[Cognitive processes and neuronal networks]

It is clear that computers are but a poor brain models: the nervous system has many "processors" (neurons) in parallel, whereas von Neuman's machines work sequentially on a single processor. In complex systems, emergent properties cannot be inferred from the behaviour of single elements. Anthills display collective "meaningful" moves, while each ant seems to obey local interactions only. Likewise, large parallel networks of processing elements elicit emergent properties. Like brains, some of them are self-organizing systems. In large parallel processing networks, each unit performs an elementary computation: adding inputs from other units. Large nets display surprising spontaneous computational abilities: associative memories, classes, generalizations may be seen as emergent properties of the network. Symbols are dynamical entities, whose handing is driven by local interactions of activation/inhibition of related representations. In such models, representations (memories) are distributed in the whole network, as stable configurations. Indeed, the basic properties of representation in connectionist models seem closer to human mental objects than the classic Artificial Intelligence concepts. Connectionist models have been used in many fields, namely simulations of real neural networks, pattern recognition and artificial vision, speech recognition, language understanding and knowledge representation, problem solving... Connectionist models have been thus used in neurobiology as well as cognition. One basic structure seems indeed able to account for a range of cognitive functions, from perception to problem solving and high level cognitive tasks. Nevertheless studies about "pathological" networks are yet rare, still an open field... We explore some of these fields.

Therapeutic response to a dermatologic patch and betamethasone valerate 0.1 percent cream in the management of chronic plaques in psoriasis

The efficacy of a hydrocolloid dermatologic patch (Actiderm) in conjunction with topical beta-methasone valerate 0.1 percent cream was studied in outpatients with chronic plaque-type psoriasis treated for three weeks, and observed for an additional two weeks after therapy. A significant degree (p less than 0.05) of lesion resolution occurred at the site treated with the dermatologic patch plus steroid cream, whereas sites treated with either agent alone showed mild but insignificant change. It was concluded that the patch was a highly effective adjunct in the treatment of chronic plaques of psoriasis.

[Analysis and cognitive modelling of the analogical process in psychosis]

The disturbances of cognitive processes in psychotic patients are well known: the delusional interpretation is "the inference from a right perception into a wrong concept" (Dromard), "an wrong intuition about the meaning of what is perceived, seen or heard" (H. Ey). Analogy is the very core of any cognitive process: relating a strange thing to some object already part of the experience enables to set up differences, oppositions, connections, classes. Any semantic process (something stands for another thing) originates in analogy. It is the basis of every interpretation and world's knowledge. Its soundness is by no means reliable, but for the inner strength of the analogical network and its power to integrate new objects. It's easy to fall out of the track... A wrong analogy, better, a wrong one that would not be acknowledged as a mistake, would be enough: the gap is quite narrow between interpretations leading either to understanding or to misreading, only filled through the relation of other people providing the necessary clues. The contemporary papers about cognitive process are driving towards two main trends: 1) Neuromimetic models, and the building of neuronal networks, whose emergent properties point out the basically analogical character of representations, learning and memory. 2) Cognitive models, dealing with representations and algorithms, and leading to Artificial Intelligence Programs. We tried to build a model (both cognitive and AI) of the analogical process and its psychotic disturbances. Our model describes how simple analogical problems are solved: If (A) becomes (B), what about (C)? Making up the psychological model and its AI translation led to propound the concept of Universes as sets consisting of ONE likely or relevant link between two objects, and such intrinsic of extrinsic properties of the objects as are involved in this relation. The model uses 3 different universes: Universe U1, made up of one of the possible transformation kinks from (A) to (B) and (A)'s properties involved in this actual transformation. Universe U2, made out of the likeness link between Universe U1 and (C). Universe U3, performing in fact the validation procedure of the result. The analogical reasoning goes through the three universes, along an iterative loop again and again until a nice result is found.(ABSTRACT TRUNCATED AT 400 WORDS)

[Animals and their masters. Psychological and psychopathological aspects]

Animals have always occupied a privileged place beside man and with him form a couple, a duality. In the first part the authors study the psychology of the adopted animal. Then they look at greater length into the personality of his owner, with particular insistence on the reasons for acquiring it, on the choice of animal (dog, cat, horses), on the part it plays in the life of its master, and on the latter's reaction at his companion's death. They also tackle the problem of man's abnormal behaviour in relation to animals, especially bestiality.