The antinociceptive effects of anterior pretectal stimulation in tests using thermal, mechanical and chemical noxious stimuli

Four behavioural tests have been used to study the antinociceptive effects of electrical stimulation of the anterior pretectal nucleus (APtN) in the rat. The antinociceptive effects of stimulating this nucleus, which lies dorsally in the posterior diencephalon, have recently been studied extensively but always using briefly applied heat stimuli. It is reported here that APtN stimulation effectively inhibited responses to briefly applied noxious pressure and longer-lasting noxious chemical (formalin) stimuli. Although the tail-flick reflex to noxious heat was very potently depressed by APtN stimulation, responses to noxious heat in the hot-plate test were not. Three doses of morphine were also studied with each test and it was concluded that 15 sec of 35 microA r.m.s. current into the APtN was as effective as 3-5 mg/kg morphine s.c. in the rat.     

The clinical features and prognosis of pseudoseizures diagnosed using video-EEG telemetry

A total of 110 patients underwent diagnostic evaluation for attacks of uncertain origin by means of video-EEG telemetry and had a diagnosis of pseudoseizures confirmed. Eighty-six patients (78%) were female, mean age of onset 25 years, and mean duration of attacks was 3 years. Many of the patients had erroneously been thought to be suffering from epilepsy. The attacks could be divided into two broad categories: attacks of collapse (one-third) and attacks with prominent motor activity (two-thirds). In some patients, the attacks were associated with incontinence and injury. The differential diagnosis and clinical features of the attacks are described. Additional psychiatric features were present in 52 (47%) patients. Follow-up (for a median 5 years; range, 1 to 14 years) showed that 40% of these patients stopped having pseudoseizures. This favorable outcome was associated with being female, leading an independent life, a formal psychological approach to therapy and counseling, and the absence of coexisting epilepsy, but not with the duration of pseudoepilepsy, prior episodes of pseudostatus, the coexistence of overt psychiatric disease, or the clinical features of the attacks.     

Control of detrusor hyperreflexia by the intravesical instillation of oxybutynine hydrochloride

This report deals with the control of detrusor hyperreflexia by the intravesical instillation of oxybutynin hydrochloride (OH) in 10 male and 3 female patients with complete suprasacral spinal cord lesions having clean intermittent catheterisation (CIC) because of unbalanced voiding. The indication for intravesical OH application was persisting urinary incontinence despite CIC in 11 patients and in 2 patients detrusor hypercontractility. One 5 mg tablet of OH was dissolved in distilled water and the solution was instilled into the bladder through the catheter, which has been used for urodynamics and which was then removed. Six hours later cystometry was repeated and the clinical effects were studied especially with regard to continence/incontinence and side-effects. The differences in the cystometric bladder capacity and maximum detrusor pressure before and after instillation of OH are statistically highly significant. Clinically, from those 10 patients who were incontinent between CIC before, 9 remained dry during the 6-hour period. None of the patients reported any side-effect after intravesical application of OH. However, with subsequent oral medication 8 out of 12 patients complained of typical anticholinergic side-effects. These results indicate that treatment with topical OH is an effective alternative to treating detrusor hyperreflexia, especially in patients already on CIC because of unbalanced voiding, but with persisting urinary incontinence due to detrusor hyperreflexia. OH is well absorbed from the bladder, however absorption seems to be protracted compared to oral intake.     

Limitations of efficacy of chemotherapies in schizophrenia]

The concept of treatment-resistant schizophrenia cannot be defined as this of resistant depression: schizophrenia is a long-term illness; its evolution is almost always influenced by neuroleptics--but complete recovery is rare. French psychiatry tends to use clinical-empirical criteria, while english speaking studies prefer quantitative criteria, by extended use of clinical and psycho-social scales. The definition of resistant schizophrenia by Kane et al. is a typical example of this method of work. We propose to overview the limits of neuroleptics efficiency in schizophrenia from three groups of studies: a) The effects of maintenance therapy: 24 studies of the last twenty years show that 2/3 of schizophrenics under neuroleptics maintain their remission over one or two years, opposed to less than 1/3 of those who discontinue their treatment. These data seem to be independant from the method of the study, the choice of the neuroleptic drug, the dose and the way of administration (per os or depot treatment). b) A second group of studies tries to define the clinical characteristics of treatment-resistant schizophrenia. French psychiatry uses an empirical graduation of neuroleptics clinical efficiency: these drugs are more effective on hallucinations than on delusional ideas--they are more effective on recent and acute hallucinations and delusions than on those of which course is chronic. Other studies specify predictive factors of poor response to neuroleptics, as few affective symptoms and presence of negative symptoms--a controversed factor. c) Not clinical factors of poor neuroleptics efficiency in schizophrenia begin to be studied.(ABSTRACT TRUNCATED AT 250 WORDS)     

Inhibitory effects of powerline-frequency (60-Hz) magnetic fields on pentylenetetrazol-induced seizures and mortality in rats.

The possibility that exposure to powerline frequency (60-Hz) magnetic fields might affect the form or intensity of epileptic seizures, induced by administration of pentylenetetrazol (PTZ) in rats, was examined. Male adult rats were exposed to either 60-Hz magnetic fields with intensities of up to 1.85 gauss (185 microT) or to a sham field condition, for 1 h prior to injections of PTZ (45-75 mg/kg). The subsequent seizures were monitored and recorded on videotape and any subsequent mortalities were noted. Exposure to 60-Hz magnetic fields prior to administration of PTZ was found to significantly (P less than 0.005) reduce the lethality of the drug-induced seizures. The LD50 for the sham-exposed group was 65.88 mg/kg, whereas for the 60-Hz magnetic field-exposed rats, the LD50 was 85.33 mg/kg. In some experiments exposure to the 1.0 and 1.5 gauss magnetic fields also produced significant (P less than 0.05) reductions in seizure durations. These findings suggest that acute exposure to low intensity 60-Hz magnetic fields has an inhibitory effect on the lethality and expression of PTZ-induced seizures in rats. Some possible mechanisms, which could account for these observed effects of magnetic field exposure on seizures, are discussed.     

Goal setting and recovery from alcoholism

Evaluation of alcoholism treatment effectiveness needs to be based on the healthy goals that alcoholics themselves identify as important. This research uses ethnography and grounded-theory methods to develop a model of recovering alcoholics' goal progression. The author spent 28 days in a treatment center, engaging in all patient activities, and observed and interviewed 42 participants to determine what they wanted from treatment. The research indicates that recovering alcoholics' goals develop through four stages. Certain kinds of behavior must be accomplished for an alcoholic to move from one stage to another. Behavior that facilitates and inhibits goal progression is identified.     

Indomethacin distribution in acute pharmacological response among rats

A detailed examination of quantitative relationships of pharmacological action with plasma and tissue concentrations of indomethacin has been undertaken in the rat, after single oral administration of two sustained release preparations. In this study, drug was assayed by high performance liquid chromatography, whereas antiinflammatory response was assessed through the carrageenin-induced edema test. Significant linear correlations (p less than 0.001) were found between logarithmically transformed percent inhibition of edema and logarithmically transformed plasma, as well as tissue levels of indomethacin. However, the lack of significance for partial correlation regarding tissue concentration, contrary to plasma concentration, suggests that pharmacological response is more closely related to the latter, indicating that antidematous effect is mediated via the circulating drug rather than a local action in target tissues. This assumption is further discussed from the equivalence point of view. The relevance of this type of study in the case of topical administration of indomethacin is addressed as well. Taking into account the predictive value of the rat paw edema test for clinical efficacy, relationships similar to those observed are to be expected in man. The high correlation existing between plasma concentration of indomethacin and its pharmacological effect justifies the development and use of sustained release preparations in order to improve the outcome of treatment with this nonsteroidal antiinflammatory drug.